asn1ct_parser2: Clean up error handling and reporting

Errors were reported using a throw like this:

   throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
		       [got,get_token(hd(Tokens)),expected,typereference]}}).

The attempt to tell the user what was expected was often mis-leading.
It is time-consuming and non-trival to provide correct information
of what is expected. Therefore, we will not even try. Instead we will
spend more effort to report the token where the error was discovered.

We will replace each throw with a function call:

   parse_error(Tokens).

Also add the syntax_SUITE test suite to test error reporting and to
cover all error reporting code. Remove the old c_syntax/1 test case.

Also remove all out-commented code.

26 files changed, 1134 insertions, 1414 deletions

diff --git a/lib/asn1/src/asn1ct_check.erl b/lib/asn1/src/asn1ct_check.erl
index 7ed7da2ae7..23794f789a 100644
--- a/lib/asn1/src/asn1ct_check.erl
+++ b/lib/asn1/src/asn1ct_check.erl
@@ -527,8 +527,6 @@ check_class(S = #state{mname=M,tname=T},ClassSpec)
     end;
 check_class(S, #objectclass{}=C) ->
     check_objectclass(S, C);
-check_class(_S,{poc,_ObjSet,_Params}) ->
-    'fix this later';
 check_class(S,ClassName) ->
     {RefMod,Def} = get_referenced_type(S,ClassName),
     case Def of
diff --git a/lib/asn1/src/asn1ct_parser2.erl b/lib/asn1/src/asn1ct_parser2.erl
index d1c0b7feda..7a1c7230b3 100644
--- a/lib/asn1/src/asn1ct_parser2.erl
+++ b/lib/asn1/src/asn1ct_parser2.erl
@@ -28,19 +28,26 @@
 -record(constraint, {c,e}).
 -record(identifier, {pos,val}).
 
-parse(File0, Tokens) ->
-    try do_parse(Tokens) of
+parse(File0, Tokens0) ->
+    try do_parse(Tokens0) of
 	{ok,#module{}}=Result ->
 	    Result
     catch
-	throw:{asn1_error,{Line,_Mod,Message}} ->
-	    File = filename:basename(File0),
-	    Error = {structured_error,{File,Line},?MODULE,Message},
-	    {error,[Error]}
+	throw:{asn1_error,Fun} when is_function(Fun, 0) ->
+	    handle_parse_error(File0, Fun());
+	throw:{asn1_error,{parse_error,Tokens}} ->
+	    handle_parse_error(File0, Tokens)
     after
 	clean_process_dictionary()
     end.
 
+handle_parse_error(File0, [Token|_]) ->
+    File = filename:basename(File0),
+    Line = get_line(Token),
+    Error = {structured_error,{File,Line},?MODULE,
+	     {syntax_error,get_token(Token)}},
+    {error,[Error]}.
+
 do_parse(Tokens0) ->
     {ModuleDefinition,Tokens1} = parse_ModuleDefinition(Tokens0),
     {Types,Tokens2} = parse_AssignmentList(Tokens1),
@@ -48,9 +55,7 @@ do_parse(Tokens0) ->
 	[{'END',_}|_Rest3] ->
 	    {ok,ModuleDefinition#module{typeorval=Types}};
 	_  ->
-	    throw({asn1_error,
-		   {get_line(hd(Tokens2)),get(asn1_module),
-		    [got,get_token(hd(Tokens2)),expected,'END']}})
+	    parse_error(Tokens2)
     end.
 
 clean_process_dictionary() ->
@@ -60,31 +65,10 @@ clean_process_dictionary() ->
     _ = erase(extensiondefault),
     ok.
 
-format_error(List) when is_list(List) ->
-    ["syntax error:"|print_error_message(List)].
-
-print_error_message([got,H|T]) when is_list(H) ->
-    [" got:",print_listing(H, "and"),
-     print_error_message(T)];
-print_error_message([expected,H|T]) when is_list(H) ->
-    [" expected one of:",
-     print_listing(H, "or"),
-     print_error_message(T)];
-print_error_message([H|T])  ->
-    [io_lib:format(" ~p", [H]),
-     print_error_message(T)];
-print_error_message([]) ->
-    "\n".
-
-print_listing([H1,H2|[]], AndOr) ->
-    io_lib:format(" ~p ~s ~p",[H1,AndOr,H2]);
-print_listing([H1,H2|T], AndOr) ->
-    [io_lib:format(" ~p,",[H1])|print_listing([H2|T], AndOr)];
-print_listing([H], _AndOr) ->
-    io_lib:format(" ~p", [H]);
-print_listing([],_) ->
-    [].
-
+format_error({syntax_error,Token}) when is_atom(Token) ->
+    io_lib:format("syntax error before: '~s'", [Token]);
+format_error({syntax_error,Token}) ->
+    io_lib:format("syntax error before: '~p'", [Token]).
 
 parse_ModuleDefinition([{typereference,L1,ModuleIdentifier}|Rest0]) ->
     put(asn1_module,ModuleIdentifier),
@@ -99,9 +83,7 @@ parse_ModuleDefinition([{typereference,L1,ModuleIdentifier}|Rest0]) ->
 	       [{'DEFINITIONS',_}|Rest03] ->
 		   Rest03;
 	       _ ->
-		   throw({asn1_error,{get_line(hd(Rest02)),get(asn1_module),
-				      [got,get_token(hd(Rest02)),
-				       expected,'DEFINITIONS']}})
+		   parse_error(Rest02)
 	   end,
     {TagDefault,Rest2} = 
 	case Rest of
@@ -133,12 +115,11 @@ parse_ModuleDefinition([{typereference,L1,ModuleIdentifier}|Rest0]) ->
 		     extensiondefault = ExtensionDefault,
 		     exports = Exports,
 		     imports = {imports, Imports}}, Rest6};
-	_ -> throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-				[got,get_token(hd(Rest3)),expected,"::= BEGIN"]}})
+	_ ->
+	    parse_error(Rest3)
     end;
 parse_ModuleDefinition(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,typereference]}}).
+    parse_error(Tokens).
     
 parse_Exports([{'EXPORTS',_L1},{';',_L2}|Rest]) ->
     {{exports,[]},Rest};
@@ -151,8 +132,7 @@ parse_Exports([{'EXPORTS',_L1}|Rest]) ->
 	[{';',_}|Rest3] ->    
 	    {{exports,SymbolList},Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,';']}})
+	    parse_error(Rest2)
     end;
 parse_Exports(Rest) ->
     {{exports,all},Rest}.
@@ -166,29 +146,25 @@ parse_SymbolList(Tokens,Acc) ->
 	[{',',_L1}|Rest2] ->
 	    parse_SymbolList(Rest2,[Symbol|Acc]);
 	Rest2  ->
-	    {lists:reverse([Symbol|Acc]),Rest2}
+	    {lists:reverse(Acc, [Symbol]),Rest2}
     end.
 
 parse_Symbol(Tokens) ->
     parse_Reference(Tokens).
 
 parse_Reference([{typereference,L1,TrefName},{'{',_L2},{'}',_L3}|Rest]) ->
-%    {Tref,Rest};
     {tref2Exttref(L1,TrefName),Rest};
 parse_Reference([Tref1 = {typereference,_,_},{'.',_},Tref2 = {typereference,_,_},
 		 {'{',_L2},{'}',_L3}|Rest]) ->
-%    {{Tref1,Tref2},Rest};
     {{tref2Exttref(Tref1),tref2Exttref(Tref2)},Rest};
 parse_Reference([Tref = {typereference,_L1,_TrefName}|Rest]) ->
     {tref2Exttref(Tref),Rest};
-parse_Reference([Vref = {identifier,_L1,_VName},{'{',_L2},{'}',_L3}|Rest]) ->
+parse_Reference([#identifier{}=Vref,{'{',_L2},{'}',_L3}|Rest]) ->
     {identifier2Extvalueref(Vref),Rest};
-parse_Reference([Vref = {identifier,_L1,_VName}|Rest]) ->
+parse_Reference([#identifier{}=Vref|Rest]) ->
     {identifier2Extvalueref(Vref),Rest};
 parse_Reference(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[typereference,identifier]]}}).
+    parse_error(Tokens).
 
 parse_Imports([{'IMPORTS',_L1},{';',_L2}|Rest]) ->
     {{imports,[]},Rest};
@@ -197,9 +173,8 @@ parse_Imports([{'IMPORTS',_L1}|Rest]) ->
     case Rest2 of
 	[{';',_L2}|Rest3] ->
 	    {{imports,SymbolsFromModuleList},Rest3};
-	Rest3 ->
-	    throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,';']}})
+	_ ->
+	    parse_error(Rest2)
     end;
 parse_Imports(Tokens) ->
     {{imports,[]},Tokens}.
@@ -211,10 +186,10 @@ parse_SymbolsFromModuleList(Tokens,Acc) ->
     {SymbolsFromModule,Rest} = parse_SymbolsFromModule(Tokens),
     try parse_SymbolsFromModule(Rest) of
 	{Sl,_Rest2} when is_record(Sl,'SymbolsFromModule') ->
-	    parse_SymbolsFromModuleList(Rest,[SymbolsFromModule|Acc])
+	    parse_SymbolsFromModuleList(Rest, [SymbolsFromModule|Acc])
     catch
 	throw:{asn1_error,_} ->
-	    {lists:reverse([SymbolsFromModule|Acc]),Rest}
+	    {lists:reverse(Acc, [SymbolsFromModule]),Rest}
     end.
     
 parse_SymbolsFromModule(Tokens) ->
@@ -228,93 +203,111 @@ parse_SymbolsFromModule(Tokens) ->
 	end,
     {SymbolList,Rest} = parse_SymbolList(Tokens),
     case Rest of
-	[{'FROM',_L1},Tref = {typereference,_,Name},Ref={identifier,_L2,_Id},C={',',_}|Rest2] ->
-	    NewSymbolList = lists:map(SetRefModuleName(Name),SymbolList),
+	[{'FROM',_L1},{typereference,_,Name}=Tref|
+	 [#identifier{},{',',_}|_]=Rest2] ->
+	    NewSymbolList = lists:map(SetRefModuleName(Name), SymbolList),
 	    {#'SymbolsFromModule'{symbols=NewSymbolList,
-				  module=tref2Exttref(Tref)},[Ref,C|Rest2]};
+				  module=tref2Exttref(Tref)},Rest2};
 
 	%% This a special case when there is only one Symbol imported
 	%% from the next module. No other way to distinguish Ref from
 	%% a part of the GlobalModuleReference of Name.
-	[{'FROM',_L1},Tref = {typereference,_,Name},Ref = {identifier,_L2,_Id},From = {'FROM',_}|Rest2] ->
-	    NewSymbolList = lists:map(SetRefModuleName(Name),SymbolList),
+	[{'FROM',_L1},{typereference,_,Name}=Tref|
+	 [#identifier{},{'FROM',_}|_]=Rest2] ->
+	    NewSymbolList = lists:map(SetRefModuleName(Name), SymbolList),
 	    {#'SymbolsFromModule'{symbols=NewSymbolList,
-				  module=tref2Exttref(Tref)},[Ref,From|Rest2]};
-	[{'FROM',_L1},Tref = {typereference,_,Name},{identifier,_L2,_Id}|Rest2] ->
-	    NewSymbolList = lists:map(SetRefModuleName(Name),SymbolList),
+				  module=tref2Exttref(Tref)},Rest2};
+	[{'FROM',_L1},{typereference,_,Name}=Tref,#identifier{}|Rest2] ->
+	    NewSymbolList = lists:map(SetRefModuleName(Name), SymbolList),
 	    {#'SymbolsFromModule'{symbols=NewSymbolList,
 				  module=tref2Exttref(Tref)},Rest2}; 
-	[{'FROM',_L1},Tref = {typereference,_,Name},Brace = {'{',_}|Rest2] ->
-	    {_ObjIdVal,Rest3} = parse_ObjectIdentifierValue([Brace|Rest2]), % value not used yet, fix me
-	    NewSymbolList = lists:map(SetRefModuleName(Name),SymbolList),
+	[{'FROM',_L1},{typereference,_,Name}=Tref|[{'{',_}|_]=Rest2] ->
+	    {_ObjIdVal,Rest3} = parse_ObjectIdentifierValue(Rest2), % value not used yet, fix me
+	    NewSymbolList = lists:map(SetRefModuleName(Name), SymbolList),
 	    {#'SymbolsFromModule'{symbols=NewSymbolList,
 				  module=tref2Exttref(Tref)},Rest3}; 
-	[{'FROM',_L1},Tref = {typereference,_,Name}|Rest2] ->
-	    NewSymbolList = lists:map(SetRefModuleName(Name),SymbolList),
+	[{'FROM',_L1},{typereference,_,Name}=Tref|Rest2] ->
+	    NewSymbolList = lists:map(SetRefModuleName(Name), SymbolList),
 	    {#'SymbolsFromModule'{symbols=NewSymbolList,
 				  module=tref2Exttref(Tref)},Rest2};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,
-				['FROM typerefernece identifier ,',
-				 'FROM typereference identifier',
-				 'FROM typereference {',
-				 'FROM typereference']]}})
+	    parse_error(Rest)
     end.
 
 parse_ObjectIdentifierValue([{'{',_}|Rest]) ->
     parse_ObjectIdentifierValue(Rest,[]).
 
-parse_ObjectIdentifierValue([{number,_,Num}|Rest],Acc) ->
+parse_ObjectIdentifierValue([{number,_,Num}|Rest], Acc) ->
     parse_ObjectIdentifierValue(Rest,[Num|Acc]);
-parse_ObjectIdentifierValue([{identifier,_,Id},{'(',_}, {number,_,Num}, {')',_}|Rest],Acc) ->
+parse_ObjectIdentifierValue([#identifier{val=Id},{'(',_},{number,_,Num},{')',_}|Rest], Acc) ->
     parse_ObjectIdentifierValue(Rest,[{'NamedNumber',Id,Num}|Acc]);
-parse_ObjectIdentifierValue([{identifier,_,Id},{'(',_}, {identifier,_,Id2}, {')',_}|Rest],Acc) ->
+parse_ObjectIdentifierValue([#identifier{val=Id},{'(',_},#identifier{val=Id2},{')',_}|Rest], Acc) ->
     parse_ObjectIdentifierValue(Rest,[{'NamedNumber',Id,Id2}|Acc]);
-parse_ObjectIdentifierValue([{identifier,_,Id},{'(',_}, {typereference,_,Tref},{'.',_},{identifier,_,Id2}, {')',_}|Rest],Acc) ->
-    parse_ObjectIdentifierValue(Rest,[{'NamedNumber',Id,{'ExternalValue',Tref,Id2}}|Acc]);
-parse_ObjectIdentifierValue([Id = {identifier,_,_}|Rest],Acc) ->
-    parse_ObjectIdentifierValue(Rest,[identifier2Extvalueref(Id)|Acc]);
-parse_ObjectIdentifierValue([{'}',_}|Rest],Acc) ->
+parse_ObjectIdentifierValue([#identifier{val=Id},{'(',_},{typereference,_,Tref},{'.',_},#identifier{val=Id2}, {')',_}|Rest], Acc) ->
+    parse_ObjectIdentifierValue(Rest, [{'NamedNumber',Id,{'ExternalValue',Tref,Id2}}|Acc]);
+parse_ObjectIdentifierValue([#identifier{}=Id|Rest], Acc) ->
+    parse_ObjectIdentifierValue(Rest, [identifier2Extvalueref(Id)|Acc]);
+parse_ObjectIdentifierValue([{'}',_}|Rest], Acc) ->
     {lists:reverse(Acc),Rest};
-parse_ObjectIdentifierValue([H|_T],_Acc) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,
-			['{ some of the following }',number,'identifier ( number )',
-			 'identifier ( identifier )',
-			 'identifier ( typereference.identifier)',identifier]]}}).
+parse_ObjectIdentifierValue(Tokens, _Acc) ->
+    parse_error(Tokens).
     
-parse_AssignmentList(Tokens = [{'END',_}|_Rest]) ->
-    {[],Tokens};
-parse_AssignmentList(Tokens = [{'$end',_}|_Rest]) ->
-    {[],Tokens};
 parse_AssignmentList(Tokens) ->
-    parse_AssignmentList(Tokens,[]).
+    parse_AssignmentList(Tokens, []).
 
-parse_AssignmentList(Tokens= [{'END',_}|_Rest],Acc) ->
+parse_AssignmentList([{'END',_}|_]=Tokens, Acc) ->
     {lists:reverse(Acc),Tokens};
-parse_AssignmentList(Tokens= [{'$end',_}|_Rest],Acc) ->
+parse_AssignmentList([{'$end',_}|_]=Tokens, Acc) ->
     {lists:reverse(Acc),Tokens};
 parse_AssignmentList(Tokens0, Acc) ->
     {Assignment,Tokens} = parse_Assignment(Tokens0),
     parse_AssignmentList(Tokens, [Assignment|Acc]).
 
-parse_Assignment(Tokens) ->
-    Flist = [fun parse_TypeAssignment/1,
-	     fun parse_ValueAssignment/1,
-	     fun parse_ObjectClassAssignment/1,
-	     fun parse_ObjectAssignment/1,
-	     fun parse_ObjectSetAssignment/1,
-	     fun parse_ParameterizedAssignment/1,
+parse_Assignment([{typereference,L1,Name},{'::=',_}|Tokens0]) ->
+    %% 1) Type ::= TypeDefinition
+    %% 2) CLASS-NAME ::= CLASS {...}
+    Flist = [{type,fun parse_Type/1},
+	     {class,fun parse_ObjectClass/1}],
+    case parse_or_tag(Tokens0, Flist) of
+	{{type,Type},Tokens} ->
+	    %% TypeAssignment
+	    {#typedef{pos=L1,name=Name,typespec=Type},Tokens};
+	{{class,Type},Tokens} ->
+	    %% ObjectClassAssignment
+	    {#classdef{pos=L1,name=Name,module=resolve_module(Type),
+		       typespec=Type},Tokens}
+    end;
+parse_Assignment([{typereference,_,_},{'{',_}|_]=Tokens) ->
+    %% 1) Type{...} ::= ...
+    %% 2) ValueSet{...} Type ::= ...
+    %%    ObjectSet{...} CLASS-NAME ::= CLASS {...}
+    %% 3) CLASS-NAME{...} ::= CLASS {...}
+    %% A parameterized value set and and a parameterized object set
+    %% cannot be distinguished from each other without type information.
+    Flist = [fun parse_ParameterizedTypeAssignment/1,
+	     fun parse_ParameterizedValueSetTypeAssignment/1,
+	     fun parse_ParameterizedObjectClassAssignment/1],
+    parse_or(Tokens, Flist);
+parse_Assignment([{typereference,_,_}|_]=Tokens) ->
+    %% 1) ObjectSet CLASS-NAME ::= ...
+    %% 2) ValueSet Type ::= ...
+    Flist = [fun parse_ObjectSetAssignment/1,
 	     fun parse_ValueSetTypeAssignment/1],
-    try parse_or(Tokens, Flist) of
-	{_,_}=Result ->
-	    Result
-    catch
-	throw:{asn1_assignment_error,Reason} ->
-	    throw({asn1_error,Reason})
-    end.
-
+    parse_or(Tokens, Flist);
+parse_Assignment([#identifier{},{'{',_}|_]=Tokens) ->
+    %% 1) value{...} Type ::= ...
+    %% 2) object{...} CLASS-NAME ::= ...
+    Flist = [fun parse_ParameterizedValueAssignment/1,
+	     fun parse_ParameterizedObjectAssignment/1],
+    parse_or(Tokens, Flist);
+parse_Assignment([#identifier{}|_]=Tokens) ->
+    %% 1) value Type ::= ...
+    %% 2) object CLASS-NAME ::= ...
+    Flist = [fun parse_ValueAssignment/1,
+	     fun parse_ObjectAssignment/1],
+    parse_or(Tokens, Flist);
+parse_Assignment(Tokens) ->
+    parse_error(Tokens).
 
 parse_or(Tokens,Flist) ->
 	parse_or(Tokens,Flist,[]).
@@ -324,13 +317,11 @@ parse_or(Tokens, [Fun|Funs], ErrList) when is_function(Fun, 1) ->
 	{_,Rest}=Result when is_list(Rest) ->
 	    Result
     catch
-	throw:{asn1_error,_}=AsnErr ->
-	    parse_or(Tokens, Funs, [AsnErr|ErrList]);
-	  throw:{asn1_assignment_error,_}=AsnErr ->
-	    parse_or(Tokens, Funs, [AsnErr|ErrList])
+	throw:{asn1_error,Error} ->
+	    parse_or(Tokens, Funs, [Error|ErrList])
     end;
 parse_or(_Tokens, [], ErrList) ->
-    throw(prioritize_error(ErrList)).
+    throw({asn1_error,fun() -> prioritize_error(ErrList) end}).
 
 parse_or_tag(Tokens, Flist) ->
     parse_or_tag(Tokens, Flist, []).
@@ -340,23 +331,26 @@ parse_or_tag(Tokens, [{Tag,Fun}|Funs], ErrList) when is_function(Fun, 1) ->
 	{Parsed,Rest} when is_list(Rest) ->
 	    {{Tag,Parsed},Rest}
     catch
-	throw:{asn1_error,_}=AsnErr ->
-	    parse_or_tag(Tokens, Funs, [AsnErr|ErrList])
+	throw:{asn1_error,Error} ->
+	    parse_or_tag(Tokens, Funs, [Error|ErrList])
     end;
 parse_or_tag(_Tokens, [], ErrList) ->
-    throw(prioritize_error(ErrList)).
+    throw({asn1_error,fun() -> prioritize_error(ErrList) end}).
+
+prioritize_error(Errors0) ->
+    Errors1 = prioritize_error_1(Errors0),
+    Errors2 = [{length(L),L} || L <- Errors1],
+    Errors = lists:sort(Errors2),
+    [Res|_] = [L || {_,L} <- Errors],
+    Res.
+
+prioritize_error_1([F|T]) when is_function(F, 0) ->
+    [F()|prioritize_error_1(T)];
+prioritize_error_1([{parse_error,Tokens}|T]) ->
+    [Tokens|prioritize_error_1(T)];
+prioritize_error_1([]) ->
+    [].
 
-parse_TypeAssignment([{typereference,L1,Tref},{'::=',_}|Rest]) ->	
-    {Type,Rest2} = parse_Type(Rest),
-    {#typedef{pos=L1,name=Tref,typespec=Type},Rest2};
-parse_TypeAssignment([H1,H2|_Rest]) ->
-    throw({asn1_assignment_error,{get_line(H1),get(asn1_module),
-				  [got,[get_token(H1),get_token(H2)], expected,
-				   typereference,'::=']}});
-parse_TypeAssignment([H|_T]) ->
-    throw({asn1_assignment_error,{get_line(H),get(asn1_module),
-				  [got,get_token(H),expected,
-				   typereference]}}).
 
 %% parse_Type(Tokens) -> Ret
 %%
@@ -366,9 +360,8 @@ parse_TypeAssignment([H|_T]) ->
 %%
 parse_Type(Tokens) ->
     {Tag,Rest3} = case Tokens of
-		      [Lbr= {'[',_}|Rest] ->
-			  parse_Tag([Lbr|Rest]);
-		      Rest-> {[],Rest}
+		      [{'[',_}|_] -> parse_Tag(Tokens);
+		      _ -> {[],Tokens}
 		  end,
     {Tag2,Rest4} = case Rest3 of
 		       [{'IMPLICIT',_}|Rest31] when is_record(Tag,tag)->
@@ -380,7 +373,9 @@ parse_Type(Tokens) ->
 		       Rest31 ->
 			   {Tag,Rest31}
 		   end,
-    Flist = [fun parse_BuiltinType/1,fun parse_ReferencedType/1,fun parse_TypeWithConstraint/1],
+    Flist = [fun parse_BuiltinType/1,
+	     fun parse_ReferencedType/1,
+	     fun parse_TypeWithConstraint/1],
     {Type,Rest5} = parse_or(Rest4, Flist),
     case Rest5 of
 	[{'(',_}|_] ->
@@ -399,8 +394,7 @@ parse_BuiltinType([{'BIT',_},{'STRING',_}|Rest]) ->
 		[{'}',_}|Rest4] ->
 		    {#type{def={'BIT STRING',NamedNumberList}},Rest4};
 		_ ->
-		    throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-				       [got,get_token(hd(Rest3)),expected,'}']}})
+		    parse_error(Rest3)
 	    end;
 	 _ ->
 	    {#type{def={'BIT STRING',[]}},Rest}
@@ -415,41 +409,33 @@ parse_BuiltinType([{'CHARACTER',_},{'STRING',_}|Rest]) ->
     {#type{def='CHARACTER STRING'},Rest};
 
 parse_BuiltinType([{'CHOICE',_},{'{',_}|Rest]) ->
-    {AlternativeTypeLists,Rest2} = parse_AlternativeTypeLists(Rest),
-    AlternativeTypeLists1 =
-	lists:filter(fun(#'ExtensionAdditionGroup'{}) -> false;
-			('ExtensionAdditionGroupEnd') -> false;
-			(_) -> true
-		     end,AlternativeTypeLists),
+    {L0,Rest2} = parse_AlternativeTypeLists(Rest),
     case Rest2 of
 	[{'}',_}|Rest3] ->
-	    AlternativeTypeLists2 =
-		case {[Ext||Ext = #'EXTENSIONMARK'{} <- AlternativeTypeLists1],
-		      get(extensiondefault)} of
-		    {[],'IMPLIED'} ->  AlternativeTypeLists1 ++ [#'EXTENSIONMARK'{}];
-		    _ -> AlternativeTypeLists1
+	    NeedExt = not lists:keymember('EXTENSIONMARK', 1, L0) andalso
+		get(extensiondefault) =:= 'IMPLIED',
+	    L = case NeedExt of
+		    true ->
+			L0 ++ [#'EXTENSIONMARK'{}];
+		    false ->
+			L0
 		end,
-
-	    {#type{def={'CHOICE',AlternativeTypeLists2}},Rest3};
+	    {#type{def={'CHOICE',L}},Rest3};
 	_  ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end;
 parse_BuiltinType([{'EMBEDDED',_},{'PDV',_}|Rest]) ->
     {#type{def='EMBEDDED PDV'},Rest};
 parse_BuiltinType([{'ENUMERATED',_},{'{',_}|Rest]) ->
-    {Enumerations,Rest2} = parse_Enumerations(Rest,get(extensiondefault)),
+    {Enumerations,Rest2} = parse_Enumerations(Rest),
     case Rest2 of
 	[{'}',_}|Rest3] ->
 	    {#type{def={'ENUMERATED',Enumerations}},Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end;
 parse_BuiltinType([{'EXTERNAL',_}|Rest]) ->
     {#type{def='EXTERNAL'},Rest};
-
-% InstanceOfType
 parse_BuiltinType([{'INSTANCE',_},{'OF',_}|Rest]) ->
     {DefinedObjectClass,Rest2} = parse_DefinedObjectClass(Rest),
     case Rest2 of
@@ -460,9 +446,6 @@ parse_BuiltinType([{'INSTANCE',_},{'OF',_}|Rest]) ->
 	_ ->
 	    {#type{def={'INSTANCE OF',DefinedObjectClass,[]}},Rest2}
     end;
-
-% parse_BuiltinType(Tokens) ->
-    
 parse_BuiltinType([{'INTEGER',_}|Rest]) ->
     case Rest of 
 	[{'{',_}|Rest2] ->
@@ -471,17 +454,13 @@ parse_BuiltinType([{'INTEGER',_}|Rest]) ->
 		[{'}',_}|Rest4] ->
 		    {#type{def={'INTEGER',NamedNumberList}},Rest4};
 		_ ->
-		    throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-				       [got,get_token(hd(Rest3)),expected,'}']}})
+		    parse_error(Rest3)
 	    end;
 	 _ ->
 	    {#type{def='INTEGER'},Rest}
     end;
 parse_BuiltinType([{'NULL',_}|Rest]) ->
     {#type{def='NULL'},Rest};
-
-% ObjectClassFieldType fix me later
-
 parse_BuiltinType([{'OBJECT',_},{'IDENTIFIER',_}|Rest]) ->
     {#type{def='OBJECT IDENTIFIER'},Rest};
 parse_BuiltinType([{'OCTET',_},{'STRING',_}|Rest]) ->
@@ -509,18 +488,14 @@ parse_BuiltinType([{'SEQUENCE',_},{'{',_},{'...',Line},{'!',_}|Rest]) ->
 		parse_ComponentTypeLists2(Rest2,[#'EXTENSIONMARK'{pos=Line}]),
 	    case Rest3 of
 		[{'}',_}|Rest4] ->
-	    {#type{def=#'SEQUENCE'{components=ComponentTypeLists}},Rest4};
+		    {#type{def=#'SEQUENCE'{components=ComponentTypeLists}},Rest4};
 		_  ->
-		    throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,'}']}})
+		    parse_error(Rest3)
 	    end
-% 	_ -> % Seq case 4,17-19,23-26 will fail here
-% 	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-% 			       [got,get_token(hd(Rest2)),expected,'}']}})
     end;
 parse_BuiltinType([{'SEQUENCE',_},{'{',_}|Rest]) ->
     {ComponentTypeLists,Rest2} = parse_ComponentTypeLists(Rest),
-    case Rest2  of
+    case Rest2 of
 	[{'}',_}|Rest3] ->
 	    ComponentTypeLists2 =
 		case {[Ext||Ext = #'EXTENSIONMARK'{} <- ComponentTypeLists],
@@ -531,25 +506,19 @@ parse_BuiltinType([{'SEQUENCE',_},{'{',_}|Rest]) ->
 	    {#type{def=#'SEQUENCE'{components = ComponentTypeLists2}},
 	     Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end;
-
-parse_BuiltinType([{'SEQUENCE',_},{'OF',_},Id={identifier,_,_},Lt={'<',_}|Rest]) ->
-%% TODO: take care of the identifier for something useful
-    {Type,Rest2} = parse_SelectionType([Id,Lt|Rest]),
-    {#type{def={'SEQUENCE OF',Type}},Rest2};
-
-parse_BuiltinType([{'SEQUENCE',_},{'OF',_},{identifier,_,_} |Rest]) ->
+parse_BuiltinType([{'SEQUENCE',_},{'OF',_}|
+		   [#identifier{},{'<',_}|_]=Tokens0]) ->
+    {Type,Tokens} = parse_SelectionType(Tokens0),
+    {#type{def={'SEQUENCE OF',Type}},Tokens};
+parse_BuiltinType([{'SEQUENCE',_},{'OF',_},#identifier{} |Rest]) ->
 %% TODO: take care of the identifier for something useful
     {Type,Rest2} = parse_Type(Rest),
     {#type{def={'SEQUENCE OF',Type}},Rest2};
-
 parse_BuiltinType([{'SEQUENCE',_},{'OF',_}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {#type{def={'SEQUENCE OF',Type}},Rest2};
-
-
 parse_BuiltinType([{'SET',_},{'{',_},{'...',Line},{'}',_}|Rest]) ->
     {#type{def=#'SET'{components=[#'EXTENSIONMARK'{pos = Line}]}},Rest};
 parse_BuiltinType([{'SET',_},{'{',_},{'...',Line},{'!',_}|Rest]) ->
@@ -561,12 +530,18 @@ parse_BuiltinType([{'SET',_},{'{',_},{'...',Line},{'!',_}|Rest]) ->
 						val = ExceptionIdentification}]}},
 	     Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    {ComponentTypeLists,Rest3}=
+		parse_ComponentTypeLists2(Rest2,[#'EXTENSIONMARK'{pos=Line}]),
+	    case Rest3 of
+		[{'}',_}|Rest4] ->
+		    {#type{def=#'SET'{components=ComponentTypeLists}},Rest4};
+		_  ->
+		    parse_error(Rest3)
+	    end
     end;
 parse_BuiltinType([{'SET',_},{'{',_}|Rest]) ->
     {ComponentTypeLists,Rest2} = parse_ComponentTypeLists(Rest),
-    case Rest2  of
+    case Rest2 of
 	[{'}',_}|Rest3] ->
 	    ComponentTypeLists2 =
 		case {[Ext||Ext = #'EXTENSIONMARK'{} <- ComponentTypeLists],
@@ -577,164 +552,128 @@ parse_BuiltinType([{'SET',_},{'{',_}|Rest]) ->
 	    {#type{def=#'SET'{components = ComponentTypeLists2}},
 	     Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end;
-
-parse_BuiltinType([{'SET',_},{'OF',_},Id={identifier,_,_},Lt={'<',_}|Rest]) ->
-%% TODO: take care of the identifier for something useful
-    {Type,Rest2} = parse_SelectionType([Id,Lt|Rest]),
-    {#type{def={'SET OF',Type}},Rest2};
-
-parse_BuiltinType([{'SET',_},{'OF',_},{identifier,_,_}|Rest]) ->
+parse_BuiltinType([{'SET',_},{'OF',_}|
+		   [#identifier{},{'<',_}|_]=Tokens0]) ->
+    {Type,Tokens} = parse_SelectionType(Tokens0),
+    {#type{def={'SET OF',Type}},Tokens};
+parse_BuiltinType([{'SET',_},{'OF',_},#identifier{}|Rest]) ->
 %%TODO: take care of the identifier for something useful
     {Type,Rest2} = parse_Type(Rest),
     {#type{def={'SET OF',Type}},Rest2};
-
 parse_BuiltinType([{'SET',_},{'OF',_}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {#type{def={'SET OF',Type}},Rest2};
-
-%% The so called Useful types
 parse_BuiltinType([{'GeneralizedTime',_}|Rest]) ->
     {#type{def='GeneralizedTime'},Rest};
 parse_BuiltinType([{'UTCTime',_}|Rest]) ->
     {#type{def='UTCTime'},Rest};
 parse_BuiltinType([{'ObjectDescriptor',_}|Rest]) ->
     {#type{def='ObjectDescriptor'},Rest};
-
-%% For compatibility with old standard
-parse_BuiltinType([{'ANY',_},{'DEFINED',_},{'BY',_},{identifier,_,Id}|Rest]) ->
+parse_BuiltinType([{'ANY',_},{'DEFINED',_},{'BY',_},#identifier{val=Id}|Rest]) ->
+    %% For compatibility with the old standard.
     {#type{def={'ANY_DEFINED_BY',Id}},Rest};
 parse_BuiltinType([{'ANY',_}|Rest]) ->
+    %% For compatibility with the old standard.
     {#type{def='ANY'},Rest};
-
 parse_BuiltinType(Tokens) ->
     parse_ObjectClassFieldType(Tokens).
-%    throw({asn1_error,unhandled_type}).
 
 
-parse_TypeWithConstraint([{'SEQUENCE',_},Lpar = {'(',_}|Rest]) ->
-    {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
+parse_TypeWithConstraint([{'SEQUENCE',_}|[{'(',_}|_]=Rest0]) ->
+    {Constraint,Rest2} = parse_Constraint(Rest0),
     Rest4 = case Rest2 of
-		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
+		[{'OF',_},#identifier{}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
 		    Rest3;
 		[{'OF',_}|Rest3] ->
 		    Rest3;
 		_ ->
-		    throw({asn1_error,
-			   {get_line(hd(Rest2)),get(asn1_module),
-			    [got,get_token(hd(Rest2)),expected,'OF']}})
+		    parse_error(Rest2)
 	    end,
     {Type,Rest5} = parse_Type(Rest4),
     {#type{def = {'SEQUENCE OF',Type},
 	   constraint = merge_constraints([Constraint])},Rest5};
 
-parse_TypeWithConstraint([{'SEQUENCE',_},{'SIZE',_},Lpar = {'(',_}|Rest]) ->
-    {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
+parse_TypeWithConstraint([{'SEQUENCE',_},{'SIZE',_}|[{'(',_}|_]=Rest0]) ->
+    {Constraint,Rest2} = parse_Constraint(Rest0),
     #constraint{c=C} = Constraint,
     Constraint2 = Constraint#constraint{c={element_set,{'SizeConstraint',C},
 					   none}},
     Rest4 = case Rest2 of
-		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
+		[{'OF',_},#identifier{}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
 		    Rest3;
 		[{'OF',_}|Rest3] ->
 		    Rest3;
 		_ ->
-		    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-				       [got,get_token(hd(Rest2)),expected,'OF']}})
+		    parse_error(Rest2)
 	    end,
     {Type,Rest5} = parse_Type(Rest4),
     {#type{def = {'SEQUENCE OF',Type}, constraint = merge_constraints([Constraint2])},Rest5};
 
-parse_TypeWithConstraint([{'SET',_},Lpar = {'(',_}|Rest]) ->
-    {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
+parse_TypeWithConstraint([{'SET',_}|[{'(',_}|_]=Rest0]) ->
+    {Constraint,Rest2} = parse_Constraint(Rest0),
     Rest4 = case Rest2 of
-		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
+		[{'OF',_},#identifier{}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
 		    Rest3;
 		[{'OF',_}|Rest3] ->
 		    Rest3;
 		_ ->
-		    throw({asn1_error,
-			   {get_line(hd(Rest2)),get(asn1_module),
-			    [got,get_token(hd(Rest2)),expected,'OF']}})
+		    parse_error(Rest2)
 	    end,
     {Type,Rest5} = parse_Type(Rest4),
     {#type{def = {'SET OF',Type},
 	   constraint = merge_constraints([Constraint])},Rest5};
 
-parse_TypeWithConstraint([{'SET',_},{'SIZE',_},Lpar = {'(',_}|Rest]) ->
-    {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
+parse_TypeWithConstraint([{'SET',_},{'SIZE',_}|[{'(',_}|_]=Rest0]) ->
+    {Constraint,Rest2} = parse_Constraint(Rest0),
     #constraint{c=C} = Constraint,
     Constraint2 = Constraint#constraint{c={element_set,
 					   {'SizeConstraint',C},none}},
     Rest4 = case Rest2 of
-		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
+		[{'OF',_},#identifier{}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
 		    Rest3;
 		[{'OF',_}|Rest3] ->
 		    Rest3;
 		_ ->
-		    throw({asn1_error,
-			   {get_line(hd(Rest2)),get(asn1_module),
-			    [got,get_token(hd(Rest2)),expected,'OF']}})
+		    parse_error(Rest2)
 	    end,
     {Type,Rest5} = parse_Type(Rest4),
     {#type{def = {'SET OF',Type},
 	   constraint = merge_constraints([Constraint2])},Rest5};
 
 parse_TypeWithConstraint(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-		       ['SEQUENCE','SEQUENCE SIZE','SET','SET SIZE'],
-		       followed,by,a,constraint]}}).
+    parse_error(Tokens).
 
 
 %% --------------------------
 
 parse_ReferencedType(Tokens) ->
-    Flist = [fun parse_DefinedType/1,
+    Flist = [fun parse_ParameterizedType/1,
+	     fun parse_DefinedType/1,
 	     fun parse_SelectionType/1,
 	     fun parse_TypeFromObject/1],
     parse_or(Tokens, Flist).
     
-parse_DefinedType(Tokens=[{typereference,_,_},{'{',_}|_Rest]) ->
-    parse_ParameterizedType(Tokens);
-parse_DefinedType(Tokens=[{typereference,L1,TypeName},
-			  T2={typereference,_,_},T3={'{',_}|Rest]) ->
-    try parse_ParameterizedType(Tokens) of
-	{_,_}=Result ->
-	    Result
-    catch
-	throw:{asn1_error,_} ->
-	    Rest2 = [T2,T3|Rest],
-	    {#type{def = #'Externaltypereference'{pos=L1,
-						  module=resolve_module(TypeName),
-						  type=TypeName}},Rest2}
-    end;
-parse_DefinedType(Tokens=[{typereference,_L1,_Module},{'.',_},
-			  {typereference,_,_TypeName},{'{',_}|_Rest]) ->
-    parse_ParameterizedType(Tokens);
-parse_DefinedType([{typereference,L1,Module},{'.',_},{typereference,_,TypeName}|Rest]) ->
-    {#type{def = #'Externaltypereference'{pos=L1,module=Module,type=TypeName}},Rest};
-parse_DefinedType([{typereference,L1,TypeName}|Rest]) ->
-    {#type{def = #'Externaltypereference'{pos=L1,module=resolve_module(TypeName),
-					  type=TypeName}},Rest};
+parse_DefinedType([{typereference,L1,Module},
+		   {'.',_},
+		   {typereference,_,TypeName}|Tokens]) ->
+    {#type{def = #'Externaltypereference'{pos=L1,module=Module,
+					  type=TypeName}},Tokens};
+parse_DefinedType([{typereference,_,_}=Tr|Tokens]) ->
+    {#type{def=tref2Exttref(Tr)},Tokens};
 parse_DefinedType(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[typereference,'typereference.typereference',
-			 'typereference typereference']]}}).
+    parse_error(Tokens).
 
-parse_SelectionType([{identifier,_,Name},{'<',_}|Rest]) ->    
+parse_SelectionType([#identifier{val=Name},{'<',_}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {#type{def={'SelectionType',Name,Type}},Rest2};
 parse_SelectionType(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'identifier <']}}).
+    parse_error(Tokens).
     
 
 resolve_module(Type) ->
@@ -747,30 +686,13 @@ resolve_module(_Type, Current, undefined) ->
 resolve_module(Type, Current, Imports) ->
     case [Mod || #'SymbolsFromModule'{symbols = S, module = Mod} <- Imports,
                  #'Externaltypereference'{type = T} <- S, 
-                 Type == T] of
+                 Type =:= T] of
         [#'Externaltypereference'{type = Mod}|_] -> Mod; 
 	%% This allows the same symbol to be imported several times
 	%% which ought to be checked elsewhere and flagged as an error
         []  -> Current
     end.
 
-%% --------------------------
-
-
-%% This should probably be removed very soon 
-% parse_ConstrainedType(Tokens) ->
-%     case (catch parse_TypeWithConstraint(Tokens)) of
-% 	{'EXIT',Reason} ->
-% 	    {Type,Rest} = parse_Type(Tokens),
-% 	    {Constraint,Rest2} = parse_Constraint(Rest),
-% 	    {Type#type{constraint=Constraint},Rest2};
-% 	{asn1_error,Reason2} ->
-% 	    {Type,Rest} = parse_Type(Tokens),
-% 	    {Constraint,Rest2} = parse_Constraint(Rest),
-% 	    {Type#type{constraint=Constraint},Rest2};
-% 	Result ->
-% 	    Result
-%     end.
 
 parse_Constraints(Tokens) ->
     parse_Constraints(Tokens,[]).
@@ -779,9 +701,9 @@ parse_Constraints(Tokens,Acc) ->
     {Constraint,Rest} = parse_Constraint(Tokens),
     case Rest of
 	[{'(',_}|_Rest2] ->
-	    parse_Constraints(Rest,[Constraint|Acc]);
+	    parse_Constraints(Rest, [Constraint|Acc]);
 	_ ->
-	    {lists:reverse([Constraint|Acc]),Rest}
+	    {lists:reverse(Acc, [Constraint]),Rest}
     end.
 
 parse_Constraint([{'(',_}|Rest]) ->
@@ -790,13 +712,9 @@ parse_Constraint([{'(',_}|Rest]) ->
     case Rest3 of
 	[{')',_}|Rest4] ->
 	    {#constraint{c=Constraint,e=Exception},Rest4};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,')']}})
-    end;
-parse_Constraint(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'(']}}).
+	[_|_] ->
+	    parse_error(Rest3)
+    end.
 
 parse_ConstraintSpec(Tokens) ->
     Flist = [fun parse_GeneralConstraint/1,
@@ -808,8 +726,7 @@ parse_ExceptionSpec([LPar={')',_}|Rest]) ->
 parse_ExceptionSpec([{'!',_}|Rest]) ->
     parse_ExceptionIdentification(Rest);
 parse_ExceptionSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,[')','!']]}}).
+    parse_error(Tokens).
 
 parse_ExceptionIdentification(Tokens) ->
     Flist = [fun parse_SignedNumber/1,
@@ -823,9 +740,8 @@ parse_TypeColonValue(Tokens) ->
 	[{':',_}|Rest2] ->
 	    {Value,Rest3} = parse_Value(Rest2),
 	    {{Type,Value},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,':']}})
+	[_|_] ->
+	    parse_error(Rest)
     end.
 
 parse_SubtypeConstraint(Tokens) ->
@@ -929,15 +845,12 @@ parse_Elements([{'(',_}|Rest]) ->
     case Rest2 of
 	[{')',_}|Rest3] ->
 	    {Elems,Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,')']}})
+	[_|_] ->
+	    parse_error(Rest2)
     end;
 parse_Elements(Tokens) ->
     Flist = [fun parse_ObjectSetElements/1,
 	     fun parse_SubtypeElements/1,
-%	     fun parse_Value/1,
-%	     fun parse_Type/1,
 	     fun parse_Object/1,
 	     fun parse_DefinedObjectSet/1],
     parse_or(Tokens, Flist).
@@ -945,34 +858,20 @@ parse_Elements(Tokens) ->
 
 %% --------------------------
 
-parse_DefinedObjectClass([{typereference,_,_ModName},{'.',_},Tr={typereference,_,_ObjClName}|Rest]) ->
-%%    {{objectclassname,ModName,ObjClName},Rest};
-%    {{objectclassname,tref2Exttref(Tr)},Rest};
-    {tref2Exttref(Tr),Rest};
+parse_DefinedObjectClass([{typereference,_,ModName},{'.',_},
+			  {typereference,Pos,Name}|Tokens]) ->
+    Ext = #'Externaltypereference'{pos=Pos,
+				   module=ModName,
+				   type=Name},
+    {Ext,Tokens};
 parse_DefinedObjectClass([Tr={typereference,_,_ObjClName}|Rest]) ->
-%    {{objectclassname,tref2Exttref(Tr)},Rest};
     {tref2Exttref(Tr),Rest};
 parse_DefinedObjectClass(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			['typereference . typereference',
-			 typereference,
-			 'TYPE-IDENTIFIER',
-			 'ABSTRACT-SYNTAX']]}}).
-
-parse_ObjectClassAssignment([{typereference,L1,ObjClName},{'::=',_}|Rest]) ->
-    {Type,Rest2} = parse_ObjectClass(Rest),
-    {#classdef{pos=L1,name=ObjClName,module=resolve_module(Type),
-	       typespec=Type},Rest2};
-parse_ObjectClassAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   'typereference ::=']}}).
+    parse_error(Tokens).
 
 parse_ObjectClass(Tokens) ->
-    Flist = [fun parse_DefinedObjectClass/1,
-	     fun parse_ObjectClassDefn/1,
-	     fun parse_ParameterizedObjectClass/1],
+    Flist = [fun parse_ObjectClassDefn/1,
+	     fun parse_DefinedObjectClass/1],
     parse_or(Tokens, Flist).
 
 parse_ObjectClassDefn([{'CLASS',_},{'{',_}|Rest]) ->
@@ -980,28 +879,39 @@ parse_ObjectClassDefn([{'CLASS',_},{'{',_}|Rest]) ->
     {WithSyntaxSpec,Rest3} = parse_WithSyntaxSpec(Rest2),
     {#objectclass{fields=Type,syntax=WithSyntaxSpec},Rest3};
 parse_ObjectClassDefn(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'CLASS {']}}).
+    parse_error(Tokens).
 
 parse_FieldSpec(Tokens) ->
     parse_FieldSpec(Tokens,[]).
 
-parse_FieldSpec(Tokens,Acc) ->
-    Flist = [fun parse_FixedTypeValueFieldSpec/1,
-	     fun parse_VariableTypeValueFieldSpec/1,
-	     fun parse_ObjectFieldSpec/1,
-	     fun parse_FixedTypeValueSetFieldSpec/1,
-	     fun parse_VariableTypeValueSetFieldSpec/1,
-	     fun parse_TypeFieldSpec/1,
-	     fun parse_ObjectSetFieldSpec/1],
-    case parse_or(Tokens, Flist) of
+parse_FieldSpec(Tokens0, Acc) ->
+    Fl = case Tokens0 of
+	     [{valuefieldreference,_,_}|_] ->
+		 %% 1) &field Type
+		 %%    &object CLASS-NAME
+		 %% 2) &field &FieldName
+		 %% A fixed type field cannot be distinguished from
+		 %% an object field without type information.
+		 [fun parse_FixedTypeValueFieldSpec/1,
+		  fun parse_VariableTypeValueFieldSpec/1];
+	     [{typefieldreference,_,_}|_] ->
+		 %% 1) &Set Type
+		 %%    &ObjectSet CLASS-NAME
+		 %% 2) &Set &FieldName
+		 %% 3) &Type
+		 %% A value set and an object cannot be distinguished
+		 %% without type information.
+		 [fun parse_FixedTypeValueSetFieldSpec/1,
+		  fun parse_VariableTypeValueSetFieldSpec/1,
+		  fun parse_TypeFieldSpec/1];
+	     [_|_] ->
+		 parse_error(Tokens0)
+	 end,
+    case parse_or(Tokens0, Fl) of
 	{Type,[{'}',_}|Rest]} ->
-	    {lists:reverse([Type|Acc]),Rest};
+	    {lists:reverse(Acc, [Type]),Rest};
 	{Type,[{',',_}|Rest2]} ->
-	    parse_FieldSpec(Rest2,[Type|Acc]);
-	{_,[H|_T]}  ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'}']}})
+	    parse_FieldSpec(Rest2, [Type|Acc])
     end.
 
 parse_PrimitiveFieldName([{typefieldreference,_,FieldName}|Rest]) ->
@@ -1009,9 +919,7 @@ parse_PrimitiveFieldName([{typefieldreference,_,FieldName}|Rest]) ->
 parse_PrimitiveFieldName([{valuefieldreference,_,FieldName}|Rest]) ->
     {{valuefieldreference,FieldName},Rest};
 parse_PrimitiveFieldName(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[typefieldreference,valuefieldreference]]}}).
+    parse_error(Tokens).
 
 parse_FieldName(Tokens) ->
     {Field,Rest} = parse_PrimitiveFieldName(Tokens),
@@ -1023,7 +931,7 @@ parse_FieldName([{'.',_}|Rest0],Acc) ->
 parse_FieldName(Tokens, Acc) ->
     {lists:reverse(Acc),Tokens}.
     
-parse_FixedTypeValueFieldSpec([{valuefieldreference,L1,VFieldName}|Rest]) ->
+parse_FixedTypeValueFieldSpec([{valuefieldreference,_,VFieldName}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {Unique,Rest3} = 
 	case Rest2 of
@@ -1033,103 +941,61 @@ parse_FixedTypeValueFieldSpec([{valuefieldreference,L1,VFieldName}|Rest]) ->
 		{undefined,Rest2}
 	end,
     {OptionalitySpec,Rest5} = parse_ValueOptionalitySpec(Rest3),
-    case {Unique,Rest5} of
-	{'UNIQUE',[{Del,_}|_]} when Del =:= ','; Del =:= '}' ->
-	    {{fixedtypevaluefield,VFieldName,Type,Unique,
-	      OptionalitySpec},Rest5};
-	{_,[{Del,_}|_]} when Del =:= ','; Del =:= '}'  ->
-	    {{object_or_fixedtypevalue_field,VFieldName,Type,Unique,OptionalitySpec},Rest5};
-	_ ->
-	    throw({asn1_error,{L1,get(asn1_module),
-			       [got,get_token(hd(Rest5)),expected,[',','}']]}})
-    end;
-parse_FixedTypeValueFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,valuefieldreference]}}).
+    case is_end_delimiter(Rest5) of
+	false -> parse_error(Rest5);
+	true -> ok
+    end,
+    Tag = case Unique of
+	      'UNIQUE' -> fixedtypevaluefield;
+	      _ -> object_or_fixedtypevalue_field
+	  end,
+    {{Tag,VFieldName,Type,Unique,OptionalitySpec},Rest5}.
+
+parse_VariableTypeValueFieldSpec([{valuefieldreference,_,VFieldName}|Rest0]) ->
+    {FieldRef,Rest1} = parse_FieldName(Rest0),
+    {OptionalitySpec,Rest} = parse_ValueOptionalitySpec(Rest1),
+    case is_end_delimiter(Rest) of
+	true ->
+	    {{variabletypevaluefield,VFieldName,FieldRef,OptionalitySpec},
+	     Rest};
+	false ->
+	    parse_error(Rest)
+    end.
 
-parse_VariableTypeValueFieldSpec([{valuefieldreference,L,VFieldName}|Rest]) ->
-    {FieldRef,Rest2} = parse_FieldName(Rest),
-    {OptionalitySpec,Rest3} = parse_ValueOptionalitySpec(Rest2),
-    case Rest3 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{variabletypevaluefield,VFieldName,FieldRef,OptionalitySpec},Rest3};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			   [got,get_token(hd(Rest3)),expected,[',','}']]}})
-    end;
-parse_VariableTypeValueFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,valuefieldreference]}}).
+parse_TypeFieldSpec([{typefieldreference,_,Name}|Rest0]) ->
+    {OptionalitySpec,Rest} = parse_TypeOptionalitySpec(Rest0),
+    case is_end_delimiter(Rest) of
+	true ->
+	    {{typefield,Name,OptionalitySpec},Rest};
+	false ->
+	    parse_error(Rest)
+    end.
 
-parse_ObjectFieldSpec([{valuefieldreference,L,VFieldName}|Rest]) ->
-    {Class,Rest2} = parse_DefinedObjectClass(Rest),
-    {OptionalitySpec,Rest3} = parse_ObjectOptionalitySpec(Rest2),
-    case Rest3 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{objectfield,VFieldName,Class,undefined,OptionalitySpec},Rest3};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			   [got,get_token(hd(Rest3)),expected,[',','}']]}})
-    end;
-parse_ObjectFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,valuefieldreference]}}).
+parse_FixedTypeValueSetFieldSpec([{typefieldreference,_,Name}|Rest0]) ->
+    {Type,Rest1} = parse_Type(Rest0),
+    {OptionalitySpec,Rest} = parse_ValueSetOptionalitySpec(Rest1),
+    case is_end_delimiter(Rest) of
+	true ->
+	    {{objectset_or_fixedtypevalueset_field,Name,Type,
+	      OptionalitySpec},Rest};
+	false ->
+	    parse_error(Rest)
+    end.
 
-parse_TypeFieldSpec([{typefieldreference,L,TFieldName}|Rest]) ->
-    {OptionalitySpec,Rest2} = parse_TypeOptionalitySpec(Rest),
-    case Rest2 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{typefield,TFieldName,OptionalitySpec},Rest2};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,[',','}']]}})
-    end;
-parse_TypeFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,typefieldreference]}}).
+parse_VariableTypeValueSetFieldSpec([{typefieldreference,_,Name}|Rest0]) ->
+    {FieldRef,Rest1} = parse_FieldName(Rest0),
+    {OptionalitySpec,Rest} = parse_ValueSetOptionalitySpec(Rest1),
+    case is_end_delimiter(Rest) of
+	true ->
+	    {{variabletypevaluesetfield,Name,FieldRef,OptionalitySpec},
+	     Rest};
+	false ->
+	    parse_error(Rest)
+    end.
 
-parse_FixedTypeValueSetFieldSpec([{typefieldreference,L,TFieldName}|Rest]) ->
-    {Type,Rest2} = parse_Type(Rest),
-    {OptionalitySpec,Rest3} = parse_ValueSetOptionalitySpec(Rest2),
-    case Rest3 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{objectset_or_fixedtypevalueset_field,TFieldName,Type,
-	      OptionalitySpec},Rest3};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,[',','}']]}})
-    end;  
-parse_FixedTypeValueSetFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,typefieldreference]}}).
-
-parse_VariableTypeValueSetFieldSpec([{typefieldreference,L,TFieldName}|Rest]) ->
-    {FieldRef,Rest2} = parse_FieldName(Rest),
-    {OptionalitySpec,Rest3} = parse_ValueSetOptionalitySpec(Rest2),
-    case Rest3 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{variabletypevaluesetfield,TFieldName,FieldRef,OptionalitySpec},Rest3};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,[',','}']]}})
-    end; 
-parse_VariableTypeValueSetFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,typefieldreference]}}).
-
-parse_ObjectSetFieldSpec([{typefieldreference,L,TFieldName}|Rest]) ->
-    {Class,Rest2} = parse_DefinedObjectClass(Rest),
-    {OptionalitySpec,Rest3} = parse_ObjectSetOptionalitySpec(Rest2),
-    case Rest3 of
-	[{Del,_}|_] when Del =:= ','; Del =:= '}' ->
-	    {{objectsetfield,TFieldName,Class,OptionalitySpec},Rest3};
-	_ ->
-	    throw({asn1_error,{L,get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,[',','}']]}})
-    end;  
-parse_ObjectSetFieldSpec(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,typefieldreference]}}).
+is_end_delimiter([{',',_}|_]) -> true;
+is_end_delimiter([{'}',_}|_]) -> true;
+is_end_delimiter([_|_]) -> false.
 
 parse_ValueOptionalitySpec(Tokens)->
     case Tokens of
@@ -1140,15 +1006,6 @@ parse_ValueOptionalitySpec(Tokens)->
 	_  -> {'MANDATORY',Tokens}
     end.
 
-parse_ObjectOptionalitySpec(Tokens) ->
-    case Tokens of
-	[{'OPTIONAL',_}|Rest] -> {'OPTIONAL',Rest};
-	[{'DEFAULT',_}|Rest] ->
-	    {Object,Rest2} = parse_Object(Rest),
-	    {{'DEFAULT',Object},Rest2};
-	_  -> {'MANDATORY',Tokens}
-    end.
-
 parse_TypeOptionalitySpec(Tokens) ->
     case Tokens of
 	[{'OPTIONAL',_}|Rest] -> {'OPTIONAL',Rest};
@@ -1167,36 +1024,24 @@ parse_ValueSetOptionalitySpec(Tokens) ->
 	_  -> {'MANDATORY',Tokens}
     end.
 
-parse_ObjectSetOptionalitySpec(Tokens) ->
-        case Tokens of
-	[{'OPTIONAL',_}|Rest] -> {'OPTIONAL',Rest};
-	[{'DEFAULT',_}|Rest] ->
-	    {ObjectSet,Rest2} = parse_ObjectSet(Rest),
-	    {{'DEFAULT',ObjectSet},Rest2};
-	_  -> {'MANDATORY',Tokens}
-    end.
-
 parse_WithSyntaxSpec([{'WITH',_},{'SYNTAX',_}|Rest]) ->
     {SyntaxList,Rest2} = parse_SyntaxList(Rest),
     {{'WITH SYNTAX',SyntaxList},Rest2};
 parse_WithSyntaxSpec(Tokens) ->
     {[],Tokens}.
 
-parse_SyntaxList([{'{',_},{'}',_}|Rest]) ->
-    {[],Rest};
 parse_SyntaxList([{'{',_}|Rest]) ->
     parse_SyntaxList(Rest,[]);
 parse_SyntaxList(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,['{}','{']]}}).
+    parse_error(Tokens).
 
-parse_SyntaxList(Tokens,Acc) ->
+parse_SyntaxList(Tokens, Acc) ->
     {SyntaxList,Rest} = parse_TokenOrGroupSpec(Tokens),
     case Rest of
 	[{'}',_}|Rest2] -> 
-	    {lists:reverse([SyntaxList|Acc]),Rest2};
+	    {lists:reverse(Acc, [SyntaxList]),Rest2};
 	_ ->
-	    parse_SyntaxList(Rest,[SyntaxList|Acc])
+	    parse_SyntaxList(Rest, [SyntaxList|Acc])
     end.
 
 parse_TokenOrGroupSpec(Tokens) ->
@@ -1204,21 +1049,19 @@ parse_TokenOrGroupSpec(Tokens) ->
 	     fun parse_OptionalGroup/1],
     parse_or(Tokens, Flist).
 
-parse_RequiredToken([{typereference,L1,WordName}|Rest]) ->
+parse_RequiredToken([{typereference,_,WordName}|Rest]=Tokens) ->
     case is_word(WordName) of
 	false ->
-	    throw({asn1_error,{L1,get(asn1_module),
-			       [got,WordName,expected,a,'Word']}});
+	    parse_error(Tokens);
 	true ->
 	    {WordName,Rest}
     end;
 parse_RequiredToken([{',',L1}|Rest]) ->
     {{',',L1},Rest};
-parse_RequiredToken([{WordName,L1}|Rest]) ->
+parse_RequiredToken([{WordName,_}|Rest]=Tokens) ->
     case is_word(WordName) of
 	false ->
-	    throw({asn1_error,{L1,get(asn1_module),
-			       [got,WordName,expected,a,'Word']}});
+	    parse_error(Tokens);
 	true ->
 	    {WordName,Rest}
     end;
@@ -1228,7 +1071,9 @@ parse_RequiredToken(Tokens) ->
 parse_OptionalGroup([{'[',_}|Rest]) ->
     {Spec,Rest2} = parse_TokenOrGroupSpec(Rest),
     {SpecList,Rest3} = parse_OptionalGroup(Rest2,[Spec]),
-    {SpecList,Rest3}.
+    {SpecList,Rest3};
+parse_OptionalGroup(Tokens) ->
+    parse_error(Tokens).
 
 parse_OptionalGroup([{']',_}|Rest],Acc) ->
     {lists:reverse(Acc),Rest};
@@ -1236,43 +1081,34 @@ parse_OptionalGroup(Tokens,Acc) ->
     {Spec,Rest} = parse_TokenOrGroupSpec(Tokens),
     parse_OptionalGroup(Rest,[Spec|Acc]).
 
-parse_DefinedObject([Id={identifier,_,_ObjName}|Rest]) ->
+parse_DefinedObject([#identifier{}=Id|Rest]) ->
     {{object,identifier2Extvalueref(Id)},Rest};
-parse_DefinedObject([{typereference,L1,ModName},{'.',_},{identifier,_,ObjName}|Rest]) ->
+parse_DefinedObject([{typereference,L1,ModName},{'.',_},#identifier{val=ObjName}|Rest]) ->
     {{object, #'Externaltypereference'{pos=L1,module=ModName,type=ObjName}},Rest};
 parse_DefinedObject(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-		       [identifier,'typereference.identifier']]}}).
+    parse_error(Tokens).
 
-parse_ObjectAssignment([{identifier,L1,ObjName}|Rest]) ->
+parse_ObjectAssignment([#identifier{pos=L1,val=ObjName}|Rest]) ->
     {Class,Rest2} = parse_DefinedObjectClass(Rest),
     case Rest2 of
 	[{'::=',_}|Rest3] ->
 	    {Object,Rest4} = parse_Object(Rest3),
 	    {#typedef{pos=L1,name=ObjName,
 		      typespec=#'Object'{classname=Class,def=Object}},Rest4};
-	[H|_T]  -> 
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}});
-	Other ->
-	    throw({asn1_error,{L1,get(asn1_module),
-			       [got,Other,expected,'::=']}})
-    end;
-parse_ObjectAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,identifier]}}).
-
+	_ ->
+	    parse_error(Rest2)
+    end.
 
 %% parse_Object(Tokens) -> Ret
 %% Tokens    = [Tok]
 %% Tok       = tuple()
 %% Ret       = {object,_} | {object, _, _}
 parse_Object(Tokens) ->
-    Flist=[fun parse_ObjectDefn/1,
-	   fun parse_ObjectFromObject/1,
-	   fun parse_ParameterizedObject/1,
-	   fun parse_DefinedObject/1],
+    %% The ObjectFromObject production is not included here,
+    %% since it will have been catched by the ValueFromObject
+    %% before we reach this point.
+    Flist = [fun parse_ObjectDefn/1,
+	     fun parse_DefinedObject/1],
     parse_or(Tokens, Flist).
 
 parse_ObjectDefn(Tokens) ->
@@ -1280,24 +1116,20 @@ parse_ObjectDefn(Tokens) ->
 	   fun parse_DefinedSyntax/1],
     parse_or(Tokens, Flist).
 
-parse_DefaultSyntax([{'{',_},{'}',_}|Rest]) ->
-    {{object,defaultsyntax,[]},Rest};
 parse_DefaultSyntax([{'{',_}|Rest]) ->
     parse_DefaultSyntax(Rest,[]);
 parse_DefaultSyntax(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,['{}','{']]}}).
+    parse_error(Tokens).
 
-parse_DefaultSyntax(Tokens,Acc) ->
+parse_DefaultSyntax(Tokens, Acc) ->
     {Setting,Rest} = parse_FieldSetting(Tokens),
     case Rest of
 	[{',',_}|Rest2] ->
 	    parse_DefaultSyntax(Rest2,[Setting|Acc]);
 	[{'}',_}|Rest3] ->
-	    {{object,defaultsyntax,lists:reverse([Setting|Acc])},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,[',','}']]}})
+	    {{object,defaultsyntax,lists:reverse(Acc, [Setting])},Rest3};
+	_ ->
+	    parse_error(Rest)
     end.
 
 parse_FieldSetting(Tokens) ->
@@ -1307,9 +1139,8 @@ parse_FieldSetting(Tokens) ->
 
 parse_DefinedSyntax([{'{',_}|Rest]) ->
     parse_DefinedSyntax(Rest, []);
-parse_DefinedSyntax([H|_]) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,['{']]}}).
+parse_DefinedSyntax(Tokens) ->
+    parse_error(Tokens).
 
 parse_DefinedSyntax(Tokens,Acc) ->
     case Tokens of
@@ -1325,8 +1156,8 @@ parse_DefinedSyntax(Tokens,Acc) ->
 %% Literal ::= word | ','
 %% Setting ::= Type | Value | ValueSet | Object | ObjectSet
 %% word equals typereference, but no lower cases
-parse_DefinedSyntaxToken([{',',L1}|Rest]) ->
-    {{',',L1},Rest};
+parse_DefinedSyntaxToken([{',',_}=Comma|Rest]) ->
+    {Comma,Rest};
 %% ObjectClassFieldType or a defined type with a constraint.
 %% Should also be able to parse a parameterized type. It may be
 %% impossible to distinguish between a parameterized type and a Literal
@@ -1334,17 +1165,16 @@ parse_DefinedSyntaxToken([{',',L1}|Rest]) ->
 parse_DefinedSyntaxToken([{typereference,_,_Name},{T,_}|_]=Tokens)
   when T =:= '.'; T =:= '(' ->
     parse_Setting(Tokens);
-parse_DefinedSyntaxToken(Tokens=[TRef={typereference,L1,Name}|Rest]) ->
+parse_DefinedSyntaxToken([{typereference,L1,Name}=TRef|Rest]=Tokens) ->
     case is_word(Name) of
 	false ->
 	    case lookahead_definedsyntax(Rest) of
 		word_or_setting ->
 		    {{setting,L1,tref2Exttref(TRef)},Rest};
-		_ ->
+		setting ->
 		    parse_Setting(Tokens)
 	    end;
 	true ->
-	    %% {{word_or_setting,L1,Name},Rest}
 	    {{word_or_setting,L1,tref2Exttref(TRef)},Rest}
     end;
 parse_DefinedSyntaxToken(Tokens) ->
@@ -1357,23 +1187,24 @@ parse_DefinedSyntaxToken(Tokens) ->
     end.
 
 lookahead_definedsyntax([{typereference,_,Name}|_Rest]) ->
-    case is_word(Name)  of
+    case is_word(Name) of
 	true -> word_or_setting;
-	_ -> setting
+	false -> setting
     end;
 lookahead_definedsyntax([{'}',_}|_Rest]) ->
     word_or_setting;
 lookahead_definedsyntax(_) ->
     setting.
 	    
-parse_Word([{Name,Pos}|Rest]) ->
+parse_Word([{Name,Pos}|Rest]=Tokens) ->
     case is_word(Name) of
 	false ->
-	    throw({asn1_error,{Pos,get(asn1_module),
-			       [got,Name, expected,a,'Word']}});
+	    parse_error(Tokens);
 	true ->
 	    {{word_or_setting,Pos,tref2Exttref(Pos,Name)},Rest}
-    end.
+    end;
+parse_Word(Tokens) ->
+    parse_error(Tokens).
 
 parse_Setting(Tokens) ->
     Flist = [{type_tag,fun parse_Type/1},
@@ -1389,20 +1220,6 @@ parse_Setting(Tokens) ->
 	    {Setting,Rest}
     end.
 
-%% parse_Setting(Tokens) ->
-%%     Flist = [fun parse_Type/1,
-%% 	     fun parse_Value/1,
-%% 	     fun parse_Object/1,
-%% 	     fun parse_ObjectSet/1],
-%%     case (catch parse_or(Tokens,Flist)) of
-%% 	{'EXIT',Reason} ->
-%% 	    exit(Reason);
-%% 	AsnErr = {asn1_error,_} ->
-%% 	    throw(AsnErr);
-%% 	Result ->
-%% 	    Result
-%%     end.
-
 parse_DefinedObjectSet([{typereference,L1,ModuleName},{'.',_},
 			{typereference,L2,ObjSetName}|Rest]) ->
     {{objectset,L1,#'Externaltypereference'{pos=L2,module=ModuleName,
@@ -1411,9 +1228,7 @@ parse_DefinedObjectSet([{typereference,L1,ObjSetName}|Rest]) ->
     {{objectset,L1,#'Externaltypereference'{pos=L1,module=resolve_module(ObjSetName),
 					    type=ObjSetName}},Rest};
 parse_DefinedObjectSet(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[typereference,'typereference.typereference']]}}).
+    parse_error(Tokens).
 
 parse_ObjectSetAssignment([{typereference,L1,ObjSetName}|Rest]) ->
     {Class,Rest2} = parse_DefinedObjectClass(Rest),
@@ -1423,16 +1238,9 @@ parse_ObjectSetAssignment([{typereference,L1,ObjSetName}|Rest]) ->
 	    {#typedef{pos=L1,name=ObjSetName,
 		      typespec=#'ObjectSet'{class=Class,
 					    set=ObjectSet}},Rest4};
-	[H|_T]  -> 
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-%%%	Other ->
-%%%	    throw(Other)
-    end;
-parse_ObjectSetAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest2)
+    end.
 
 %% parse_ObjectSet(Tokens) -> {Ret,Rest}
 %% Tokens    = [Tok]
@@ -1449,13 +1257,11 @@ parse_ObjectSet([{'{',_}|Rest]) ->
     case Rest2 of
 	[{'}',_}|Rest3] ->
 	    {ObjSetSpec,Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'}']}})
+	_ ->
+	    parse_error(Rest2)
     end;
 parse_ObjectSet(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_error(Tokens).
 
 parse_ObjectSetSpec([{'...',_},{',',_}|Tokens0]) ->
     {Elements,Tokens} = parse_ElementSetSpec(Tokens0),
@@ -1465,7 +1271,6 @@ parse_ObjectSetSpec([{'...',_}|Tokens]) ->
 parse_ObjectSetSpec(Tokens) ->
     parse_ElementSetSpecs(Tokens).
 
-% moved fun parse_Object/1 and fun parse_DefinedObjectSet/1 to parse_Elements
 %% parse_ObjectSetElements(Tokens) -> {Result,Rest}
 %% Result ::= {'ObjectSetFromObjects',Objects,Name} | {pos,ObjectSet,Params}
 %% Objects ::= ReferencedObjects
@@ -1475,9 +1280,7 @@ parse_ObjectSetSpec(Tokens) ->
 %% ObjectSet ::= {objectset,integer(),#'Externaltypereference'{}}
 %% Params ::= list() (see parse_ActualParameterList/1)
 parse_ObjectSetElements(Tokens) ->
-    Flist = [%fun parse_Object/1,
-	     %fun parse_DefinedObjectSet/1,
-	     fun parse_ObjectSetFromObjects/1,
+    Flist = [fun parse_ObjectSetFromObjects/1,
 	     fun parse_ParameterizedObjectSet/1],
     parse_or(Tokens, Flist).
 
@@ -1490,25 +1293,10 @@ parse_ObjectClassFieldType(Tokens) ->
 	      classname=Class,
 	      class=Class,fieldname=FieldName},
 	    {#type{def=OCFT},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'.']}})
-%%%	Other ->
-%%%	    throw(Other)
+	_ ->
+	    parse_error(Rest)
     end.
 
-%parse_ObjectClassFieldValue(Tokens) ->
-%    Flist = [fun parse_OpenTypeFieldVal/1,
-%	     fun parse_FixedTypeFieldVal/1],
-%    case (catch parse_or(Tokens,Flist)) of
-%	{'EXIT',Reason} ->
-%	    throw(Reason);
-%	AsnErr = {asn1_error,_} ->
-%	    throw(AsnErr);
-%	Result ->
-%	    Result
-%    end.
-
 parse_ObjectClassFieldValue(Tokens) ->
     parse_OpenTypeFieldVal(Tokens).
 
@@ -1518,28 +1306,10 @@ parse_OpenTypeFieldVal(Tokens) ->
 	[{':',_}|Rest2] ->
 	    {Value,Rest3} = parse_Value(Rest2),
 	    {{opentypefieldvalue,Type,Value},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,':']}})
+	_ ->
+	    parse_error(Rest)
     end.
 
-% parse_FixedTypeFieldVal(Tokens) ->
-%     parse_Value(Tokens).
-
-% parse_InformationFromObjects(Tokens) ->
-%     Flist = [fun parse_ValueFromObject/1,
-% 	     fun parse_ValueSetFromObjects/1,
-% 	     fun parse_TypeFromObject/1,
-% 	     fun parse_ObjectFromObject/1],
-%     case (catch parse_or(Tokens,Flist)) of
-% 	{'EXIT',Reason} ->
-% 	    throw(Reason);
-% 	AsnErr = {asn1_error,_} ->
-% 	    throw(AsnErr);
-% 	Result ->
-% 	    Result
-%     end.
-
 %% parse_ReferencedObjects(Tokens) -> {Result,Rest}
 %% Result    ::= DefObject | DefObjSet |
 %%               {po,DefObject,Params} | {pos,DefObjSet,Params} |
@@ -1551,11 +1321,11 @@ parse_OpenTypeFieldVal(Tokens) ->
 parse_ReferencedObjects(Tokens) ->
     Flist = [fun parse_DefinedObject/1,
 	     fun parse_DefinedObjectSet/1,
-	     fun parse_ParameterizedObject/1,
 	     fun parse_ParameterizedObjectSet/1],
     parse_or(Tokens, Flist).
 
 parse_ValueFromObject(Tokens) ->
+    %% This production also matches ObjectFromObject.
     {Objects,Rest} = parse_ReferencedObjects(Tokens),
     case Rest of
 	[{'.',_}|Rest2] ->
@@ -1564,15 +1334,10 @@ parse_ValueFromObject(Tokens) ->
 		{valuefieldreference,_} ->
 		    {{'ValueFromObject',Objects,Name},Rest3};
 		_ ->
-		    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-				       [got,typefieldreference,expected,
-					valuefieldreference]}})
+		    parse_error(Rest2)
 	    end;
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'.']}})
-%%%	Other ->
-%%%	    throw({asn1_error,{got,Other,expected,'.'}})
+	_ ->
+	    parse_error(Rest)
     end.
 
 parse_TypeFromObject(Tokens) ->
@@ -1584,26 +1349,10 @@ parse_TypeFromObject(Tokens) ->
 		{typefieldreference,_FieldName} ->
 		    {#type{def={'TypeFromObject',Objects,Name}},Rest3};
 		_ ->
-		    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-				       [got,get_token(hd(Rest2)),expected,
-					typefieldreference]}})
+		    parse_error(Rest2)
 	    end;
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'.']}})
-%%%	Other ->
-%%%	    throw({asn1_error,{got,Other,expected,'.'}})
-    end.
-
-parse_ObjectFromObject(Tokens) ->
-    {Objects,Rest} = parse_ReferencedObjects(Tokens),
-    case Rest of
-	[{'.',_}|Rest2] ->
-	    {Name,Rest3} = parse_FieldName(Rest2),
-	    {{'ObjectFromObject',Objects,Name},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'.']}})
+	_ ->
+	    parse_error(Rest)
     end.
 
 %% parse_ObjectSetFromObjects(Tokens) -> {Result,Rest}
@@ -1621,23 +1370,12 @@ parse_ObjectSetFromObjects(Tokens) ->
 		{typefieldreference,_FieldName} ->
 		    {{'ObjectSetFromObjects',Objects,Name},Rest3};
 		_ ->
-		    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-				       [got,get_token(hd(Rest2)),expected,
-					typefieldreference]}})
+		    parse_error(Rest2)
 	    end;
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'.']}})
+	_ ->
+	    parse_error(Rest)
     end.
 
-% parse_InstanceOfType([{'INSTANCE',_},{'OF',_}|Rest]) ->
-%     {Class,Rest2} = parse_DefinedObjectClass(Rest),
-%     {{'InstanceOfType',Class},Rest2}.
-
-% parse_InstanceOfValue(Tokens) ->
-%     parse_Value(Tokens).
-
-
 
 %% X.682 constraint specification
 
@@ -1656,28 +1394,23 @@ parse_UserDefinedConstraint([{'CONSTRAINED',_},
     case Rest2 of
 	[{'}',_}|Rest3] ->
 	    {{constrained_by,Param},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'}']}})
+	_ ->
+	    parse_error(Rest2)
     end;
 parse_UserDefinedConstraint(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			['CONSTRAINED BY {}','CONSTRAINED BY {']]}}).
+    parse_error(Tokens).
 
 parse_UserDefinedConstraintParameter(Tokens) ->
-    parse_UserDefinedConstraintParameter(Tokens,[]).
-parse_UserDefinedConstraintParameter(Tokens,Acc) ->
+    parse_UserDefinedConstraintParameter(Tokens, []).
+
+parse_UserDefinedConstraintParameter(Tokens0, Acc) ->
     Flist = [fun parse_GovernorAndActualParameter/1,
 	     fun parse_ActualParameter/1],
-    case parse_or(Tokens, Flist) of
-	{Result,Rest} ->
-	    case Rest of
-		[{',',_}|_Rest2] ->
-		    parse_UserDefinedConstraintParameter(Tokens,[Result|Acc]);
-		_  ->
-		    {lists:reverse([Result|Acc]),Rest}
-	    end
+    case parse_or(Tokens0, Flist) of
+	{Result,[{',',_}|Tokens]} ->
+	    parse_UserDefinedConstraintParameter(Tokens, [Result|Acc]);
+	{Result,Tokens} ->
+	    {lists:reverse(Acc, [Result]),Tokens}
     end.
 
 parse_GovernorAndActualParameter(Tokens) ->
@@ -1686,9 +1419,8 @@ parse_GovernorAndActualParameter(Tokens) ->
 	[{':',_}|Rest2] ->
 	    {Params,Rest3} = parse_ActualParameter(Rest2),
 	    {{'Governor_Params',Governor,Params},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,':']}})
+	_ ->
+	    parse_error(Rest)
     end.
 
 parse_TableConstraint(Tokens) ->
@@ -1711,20 +1443,14 @@ parse_ComponentRelationConstraint([{'{',_}|Rest]) ->
 			   {componentrelation,ObjectSet,AtNot},
 			   none},
 		    {Ret,Rest5};
-		[H|_T]  ->
-		    throw({asn1_error,{get_line(H),get(asn1_module),
-				       [got,get_token(H),expected,'}']}})
+		_ ->
+		    parse_error(Rest4)
 	    end;
-	[H|_T]  ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,
-				'ComponentRelationConstraint',ended,with,'}']}})
-%%%	Other ->
-%%%	    throw(Other)
+	_  ->
+	    parse_error(Rest2)
     end;
 parse_ComponentRelationConstraint(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_error(Tokens).
 
 parse_AtNotationList(Tokens,Acc) ->
     {AtNot,Rest} = parse_AtNotation(Tokens),
@@ -1732,7 +1458,7 @@ parse_AtNotationList(Tokens,Acc) ->
 	[{',',_}|Rest2] ->
 	    parse_AtNotationList(Rest2,[AtNot|Acc]);
 	_  ->
-	    {lists:reverse([AtNot|Acc]),Rest}
+	    {lists:reverse(Acc, [AtNot]),Rest}
     end.
 
 parse_AtNotation([{'@',_},{'.',_}|Rest]) ->
@@ -1742,20 +1468,17 @@ parse_AtNotation([{'@',_}|Rest]) ->
     {CIdList,Rest2} = parse_ComponentIdList(Rest),
     {{outermost,CIdList},Rest2};
 parse_AtNotation(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,['@','@.']]}}).
+    parse_error(Tokens).
 
 parse_ComponentIdList(Tokens) ->
     parse_ComponentIdList(Tokens,[]).
 
-parse_ComponentIdList([Id = {identifier,_,_},{'.',_}|Rest],Acc) ->
+parse_ComponentIdList([#identifier{}=Id,{'.',_}|Rest], Acc) ->
     parse_ComponentIdList(Rest,[identifier2Extvalueref(Id)|Acc]);
-parse_ComponentIdList([Id = {identifier,_,_}|Rest],Acc) ->
-    {lists:reverse([identifier2Extvalueref(Id)|Acc]),Rest};
+parse_ComponentIdList([#identifier{}=Id|Rest], Acc) ->
+    {lists:reverse(Acc, [identifier2Extvalueref(Id)]),Rest};
 parse_ComponentIdList(Tokens,_) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[identifier,'identifier.']]}}).
+    parse_error(Tokens).
 
 parse_ContentsConstraint([{'CONTAINING',_}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
@@ -1770,10 +1493,7 @@ parse_ContentsConstraint([{'ENCODED',_},{'BY',_}|Rest]) ->
     {Value,Rest2} = parse_Value(Rest),
     {{contentsconstraint,[],Value},Rest2};
 parse_ContentsConstraint(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			'CONTAINING','or','ENCODED BY']}}).
-
+    parse_error(Tokens).
 
 % X.683 Parameterization of ASN.1 specifications
 
@@ -1791,15 +1511,6 @@ parse_ActualParameter(Tokens) ->
 	     fun parse_ObjectSet/1],
     parse_or(Tokens, Flist).
 
-parse_ParameterizedAssignment(Tokens) ->
-    Flist = [fun parse_ParameterizedTypeAssignment/1,
-	     fun parse_ParameterizedValueAssignment/1,
-	     fun parse_ParameterizedValueSetTypeAssignment/1,
-	     fun parse_ParameterizedObjectClassAssignment/1,
-	     fun parse_ParameterizedObjectAssignment/1,
-	     fun parse_ParameterizedObjectSetAssignment/1],
-    parse_or(Tokens, Flist).
-
 %% parse_ParameterizedTypeAssignment(Tokens) -> Result
 %% Result = {#ptypedef{},Rest} | throw()
 parse_ParameterizedTypeAssignment([{typereference,L1,Name}|Rest]) ->
@@ -1809,18 +1520,13 @@ parse_ParameterizedTypeAssignment([{typereference,L1,Name}|Rest]) ->
 	    {Type,Rest4} = parse_Type(Rest3),
 	    {#ptypedef{pos=L1,name=Name,args=ParameterList,typespec=Type},
 	     Rest4};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-    end;
-parse_ParameterizedTypeAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest2)
+    end.
 
 %% parse_ParameterizedValueAssignment(Tokens) -> Result
 %% Result = {#pvaluedef{},Rest} | throw()
-parse_ParameterizedValueAssignment([{identifier,L1,Name}|Rest]) ->
+parse_ParameterizedValueAssignment([#identifier{pos=L1,val=Name}|Rest]) ->
     {ParameterList,Rest2} = parse_ParameterList(Rest),
     {Type,Rest3} = parse_Type(Rest2),
     case Rest3 of
@@ -1828,13 +1534,9 @@ parse_ParameterizedValueAssignment([{identifier,L1,Name}|Rest]) ->
 	    {Value,Rest5} = parse_Value(Rest4),
 	    {#pvaluedef{pos=L1,name=Name,args=ParameterList,type=Type,
 			 value=Value},Rest5};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-    end;
-parse_ParameterizedValueAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,identifier]}}).
+	_ ->
+	    parse_error(Rest3)
+    end.
 
 %% parse_ParameterizedValueSetTypeAssignment(Tokens) -> Result
 %% Result = {#pvaluesetdef{},Rest} | throw()
@@ -1846,14 +1548,9 @@ parse_ParameterizedValueSetTypeAssignment([{typereference,L1,Name}|Rest]) ->
 	    {ValueSet,Rest5} = parse_ValueSet(Rest4),
 	    {#pvaluesetdef{pos=L1,name=Name,args=ParameterList,
 			   type=Type,valueset=ValueSet},Rest5};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-    end;
-parse_ParameterizedValueSetTypeAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest3)
+    end.
 
 %% parse_ParameterizedObjectClassAssignment(Tokens) -> Result
 %% Result = {#ptypedef{},Rest} | throw()
@@ -1864,18 +1561,13 @@ parse_ParameterizedObjectClassAssignment([{typereference,L1,Name}|Rest]) ->
 	    {Class,Rest4} = parse_ObjectClass(Rest3),
 	    {#ptypedef{pos=L1,name=Name,args=ParameterList,typespec=Class},
 	     Rest4};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-    end;
-parse_ParameterizedObjectClassAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest2)
+    end.
 
 %% parse_ParameterizedObjectAssignment(Tokens) -> Result
 %% Result = {#pobjectdef{},Rest} | throw()
-parse_ParameterizedObjectAssignment([{identifier,L1,Name}|Rest]) ->
+parse_ParameterizedObjectAssignment([#identifier{pos=L1,val=Name}|Rest]) ->
     {ParameterList,Rest2} = parse_ParameterList(Rest),
     {Class,Rest3} = parse_DefinedObjectClass(Rest2),
     case Rest3 of
@@ -1883,36 +1575,9 @@ parse_ParameterizedObjectAssignment([{identifier,L1,Name}|Rest]) ->
 	    {Object,Rest5} = parse_Object(Rest4),
 	    {#pobjectdef{pos=L1,name=Name,args=ParameterList,
 			 class=Class,def=Object},Rest5};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-%%%	Other ->
-%%%	    throw(Other)
-    end;
-parse_ParameterizedObjectAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,identifier]}}).
-
-%% parse_ParameterizedObjectSetAssignment(Tokens) -> Result
-%% Result = {#pobjectsetdef{},Rest} | throw{}
-parse_ParameterizedObjectSetAssignment([{typereference,L1,Name}|Rest]) ->
-    {ParameterList,Rest2} = parse_ParameterList(Rest),
-    {Class,Rest3} = parse_DefinedObjectClass(Rest2),
-    case Rest3 of
-	[{'::=',_}|Rest4] ->
-	    {ObjectSet,Rest5} = parse_ObjectSet(Rest4),
-	    {#pobjectsetdef{pos=L1,name=Name,args=ParameterList,
-			    class=Class,def=ObjectSet},Rest5};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-%%%	Other ->
-%%%	    throw(Other)
-    end;
-parse_ParameterizedObjectSetAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest3)
+    end.
 
 %% parse_ParameterList(Tokens) -> Result
 %% Result = [Parameter]
@@ -1921,22 +1586,18 @@ parse_ParameterizedObjectSetAssignment(Tokens) ->
 %% Type = #type{}
 %% DefinedObjectClass = #'Externaltypereference'{}
 %% Reference = #'Externaltypereference'{} | #'Externalvaluereference'{}
-parse_ParameterList([{'{',_}|Rest]) ->
-    parse_ParameterList(Rest,[]);
-parse_ParameterList(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+parse_ParameterList([{'{',_}|Tokens]) ->
+    parse_ParameterList(Tokens, []).
 
 parse_ParameterList(Tokens,Acc) ->
     {Parameter,Rest} = parse_Parameter(Tokens),
     case Rest of
 	[{',',_}|Rest2] ->
-	    parse_ParameterList(Rest2,[Parameter|Acc]);
+	    parse_ParameterList(Rest2, [Parameter|Acc]);
 	[{'}',_}|Rest3] ->
-	    {lists:reverse([Parameter|Acc]),Rest3};
-	[H|_T]  ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,[',','}']]}})
+	    {lists:reverse(Acc, [Parameter]),Rest3};
+	_ ->
+	    parse_error(Rest)
     end.
 
 parse_Parameter(Tokens) ->
@@ -1950,9 +1611,8 @@ parse_ParamGovAndRef(Tokens) ->
 	[{':',_}|Rest2] ->
 	    {Ref,Rest3} = parse_Reference(Rest2),
 	    {{ParamGov,Ref},Rest3};
-	[H|_T] ->
-	   throw({asn1_error,{get_line(H),get(asn1_module),
-			      [got,get_token(H),expected,':']}})
+	_ ->
+	    parse_error(Rest)
     end.
 
 parse_ParamGovernor(Tokens) ->
@@ -1960,69 +1620,45 @@ parse_ParamGovernor(Tokens) ->
 	     fun parse_Reference/1],
     parse_or(Tokens, Flist).
 
-% parse_ParameterizedReference(Tokens) ->
-%     {Ref,Rest} = parse_Reference(Tokens),
-%     case Rest of
-% 	[{'{',_},{'}',_}|Rest2] ->
-% 	    {{ptref,Ref},Rest2};
-% 	_  ->
-% 	    {{ptref,Ref},Rest}
-%     end.
-
 parse_SimpleDefinedType([{typereference,L1,ModuleName},{'.',_},
 			 {typereference,_,TypeName}|Rest]) ->
     {#'Externaltypereference'{pos=L1,module=ModuleName,
 						 type=TypeName},Rest};
 parse_SimpleDefinedType([Tref={typereference,_,_}|Rest]) ->
-%    {#'Externaltypereference'{pos=L2,module=get(asn1_module),
-%						 type=TypeName},Rest};
     {tref2Exttref(Tref),Rest};
 parse_SimpleDefinedType(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[typereference,'typereference.typereference']]}}).
+    parse_error(Tokens).
 
 parse_SimpleDefinedValue([{typereference,L1,ModuleName},{'.',_},
-			  {identifier,_,Value}|Rest]) ->
+			  #identifier{val=Value}|Rest]) ->
     {{simpledefinedvalue,#'Externalvaluereference'{pos=L1,module=ModuleName,
 						   value=Value}},Rest};
-parse_SimpleDefinedValue([Id={identifier,_,_Value}|Rest]) ->
+parse_SimpleDefinedValue([#identifier{}=Id|Rest]) ->
     {{simpledefinedvalue,identifier2Extvalueref(Id)},Rest};
 parse_SimpleDefinedValue(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			['typereference.identifier',identifier]]}}).
+    parse_error(Tokens).
 
 parse_ParameterizedType(Tokens) ->
+    %% May also be a parameterized class.
     {Type,Rest} = parse_SimpleDefinedType(Tokens),
     {Params,Rest2} = parse_ActualParameterList(Rest),
     {#type{def={pt,Type,Params}},Rest2}.
 
 parse_ParameterizedValue(Tokens) ->
+    %% May also be a parameterized object.
     {Value,Rest} = parse_SimpleDefinedValue(Tokens),
     {Params,Rest2} = parse_ActualParameterList(Rest),
     {{pv,Value,Params},Rest2}.
 
-parse_ParameterizedObjectClass(Tokens) ->
-    {Type,Rest} = parse_DefinedObjectClass(Tokens),
-    {Params,Rest2} = parse_ActualParameterList(Rest),
-    {{poc,Type,Params},Rest2}.
-
 parse_ParameterizedObjectSet(Tokens) ->
     {ObjectSet,Rest} = parse_DefinedObjectSet(Tokens),
     {Params,Rest2} = parse_ActualParameterList(Rest),
     {{pos,ObjectSet,Params},Rest2}.
 
-parse_ParameterizedObject(Tokens) ->
-    {Object,Rest} = parse_DefinedObject(Tokens),
-    {Params,Rest2} = parse_ActualParameterList(Rest),
-    {{po,Object,Params},Rest2}.
-
 parse_ActualParameterList([{'{',_}|Rest]) ->
     parse_ActualParameterList(Rest,[]);
 parse_ActualParameterList(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_error(Tokens).
 
 parse_ActualParameterList(Tokens,Acc) ->
     {Parameter,Rest} = parse_ActualParameter(Tokens),
@@ -2030,43 +1666,22 @@ parse_ActualParameterList(Tokens,Acc) ->
 	[{',',_}|Rest2] ->
 	    parse_ActualParameterList(Rest2,[Parameter|Acc]);
 	[{'}',_}|Rest3] ->
-	    {lists:reverse([Parameter|Acc]),Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,[',','}']]}})
-%%%	Other ->
-%%%	    throw(Other)
+	    {lists:reverse(Acc, [Parameter]),Rest3};
+	_ ->
+	    parse_error(Rest)
     end.
 
-
-
-
-
-
-
-%-------------------------
-
+%% Test whether Token is allowed in a syntax list.
 is_word(Token) ->
-    case not_allowed_word(Token) of
+    List = atom_to_list(Token),
+    case not_allowed_word(List) of
 	true -> false;
-	_ ->
-	    if
-		is_atom(Token) ->
-		    Item = atom_to_list(Token),
-		    is_word(Item);
-		is_list(Token), length(Token) == 1 ->
-		    check_one_char_word(Token);
-		is_list(Token) ->
-		    [A|Rest] = Token,
-		    case check_first(A) of
-			true ->
-			    check_rest(Rest);
-			_ -> 
-			    false
-		    end
-	    end
+	false -> is_word_1(List)
     end.
 
+is_word_1([H|T]) ->
+    check_first(H) andalso check_rest(T).
+
 not_allowed_word(Name) ->
     lists:member(Name,["BIT",
 		       "BOOLEAN",
@@ -2091,255 +1706,123 @@ not_allowed_word(Name) ->
 		       "TRUE",
 		       "UNION"]).
 
-check_one_char_word([A]) when $A =< A, $Z >= A ->
-    true;
-check_one_char_word([_]) ->
-    false. %% unknown item in SyntaxList
+check_first(C) ->
+    $A =< C andalso C =< $Z.
 
-check_first(A) when $A =< A, $Z >= A ->
-    true;
-check_first(_) ->
-    false. %% unknown item in SyntaxList
-
-check_rest([R,R|_Rs]) when $- == R ->
-    false; %% two consecutive hyphens are not allowed in a word
-check_rest([R]) when $- == R ->
-    false; %% word cannot end with hyphen
-check_rest([R|Rs]) when $A=<R, $Z>=R; $-==R ->
+check_rest([R|Rs]) when $A =< R, R =< $Z; R =:= $- ->
     check_rest(Rs);
 check_rest([]) ->
     true;
 check_rest(_) ->
     false.
 
-parse_AlternativeTypeLists(Tokens) ->
-    parse_AlternativeTypeLists(Tokens,[]).
-
-parse_AlternativeTypeLists(Tokens = [{identifier,_,_}|_Rest0],Clist) ->
-    {CompList,Rest1} = parse_AlternativeTypeList(Tokens,[]),
-    parse_AlternativeTypeLists(Rest1,Clist++CompList);
-parse_AlternativeTypeLists([{'...',L1},{'!',_}|Rest02],Clist0) ->
-    {_,Rest03} = parse_ExceptionIdentification(Rest02),
-    %% Exception info is currently thrown away
-    parse_AlternativeTypeLists2(Rest03,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
-parse_AlternativeTypeLists([{',',L1},{'...',_},{'!',_}|Rest02],Clist0) when Clist0 =/= []->
-    {_,Rest03} = parse_ExceptionIdentification(Rest02),
-    %% Exception info is currently thrown away
-    parse_AlternativeTypeLists2(Rest03,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
-
-parse_AlternativeTypeLists([{',',_},{'...',L1}|Rest02],Clist0) when Clist0 =/= []->
-    parse_AlternativeTypeLists2(Rest02,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
-parse_AlternativeTypeLists([{'...',L1}|Rest02],Clist0) ->
-    parse_AlternativeTypeLists2(Rest02,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
-parse_AlternativeTypeLists(Tokens = [{'}',_L1}|_Rest02],Clist0) ->
-    {Clist0,Tokens}.
-
-parse_AlternativeTypeLists2(Tokens,Clist) ->
-    {ExtAdd,Rest} = parse_ExtensionAdditionAlternatives(Tokens,Clist),
-    {Clist2,Rest2} = parse_OptionalExtensionMarker(Rest,lists:flatten(ExtAdd)),
-    case Rest2 of
-	[{',',_}|Rest3] ->
-	    {CompList,Rest4} = parse_AlternativeTypeList(Rest3,[]),
-	    {Clist2 ++ CompList,Rest4};
-	_ ->
-	    {Clist2,Rest2}
+%%%
+%%% Parse alternative type lists for CHOICE.
+%%%
+
+parse_AlternativeTypeLists(Tokens0) ->
+    {Root,Tokens1} = parse_AlternativeTypeList(Tokens0),
+    case Tokens1 of
+	[{',',_}|Tokens2] ->
+	    {ExtMarker,Tokens3} = parse_ExtensionAndException(Tokens2),
+	    {ExtAlts,Tokens4} =	parse_ExtensionAdditionAlternatives(Tokens3),
+	    {_,Tokens} = parse_OptionalExtensionMarker(Tokens4, []),
+	    {Root++ExtMarker++ExtAlts,Tokens};
+	Tokens ->
+	    {Root,Tokens}
     end.
 
+parse_ExtensionAndException([{'...',L}|Tokens0]) ->
+    {[#'EXTENSIONMARK'{pos=L}],
+     case Tokens0 of
+	 [{'!',_}|Tokens1] ->
+	     {_,Tokens} = parse_ExceptionIdentification(Tokens1),
+	     Tokens;
+	 _ ->
+	     Tokens0
+     end}.
+
+parse_AlternativeTypeList([#identifier{}|_]=Tokens0) ->
+    {AltType,Tokens} = parse_NamedType(Tokens0),
+    parse_AlternativeTypeList_1(Tokens, [AltType]);
+parse_AlternativeTypeList(Tokens) ->
+    parse_error(Tokens).
+
+parse_AlternativeTypeList_1([{',',_}|[#identifier{}|_]=Tokens0], Acc) ->
+    {AltType,Tokens} = parse_NamedType(Tokens0),
+    parse_AlternativeTypeList_1(Tokens, [AltType|Acc]);
+parse_AlternativeTypeList_1(Tokens, Acc) ->
+    {lists:reverse(Acc),Tokens}.
 
+parse_ExtensionAdditionAlternatives([{',',_}|_]=Tokens0) ->
+    parse_ExtensionAdditionAlternativesList(Tokens0, []);
+parse_ExtensionAdditionAlternatives(Tokens) ->
+    {[],Tokens}.
 
-parse_AlternativeTypeList([{',',_},Id = {identifier,_,_}|Rest],Acc) when Acc =/= [] ->
-    {AlternativeType,Rest2} = parse_NamedType([Id|Rest]),
-    parse_AlternativeTypeList(Rest2,[AlternativeType|Acc]);
-parse_AlternativeTypeList(Tokens = [{'}',_}|_],Acc) ->
-    {lists:reverse(Acc),Tokens};
-parse_AlternativeTypeList(Tokens = [{']',_},{']',_}|_],Acc) ->
-    {lists:reverse(Acc),Tokens};
-parse_AlternativeTypeList(Tokens = [{',',_},{'...',_}|_],Acc) ->
-    {lists:reverse(Acc),Tokens};
-parse_AlternativeTypeList(Tokens,[]) ->
-    {AlternativeType,Rest} = parse_NamedType(Tokens),
-    parse_AlternativeTypeList(Rest,[AlternativeType]);
-parse_AlternativeTypeList(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['}',', identifier']]}}).
-
-parse_ExtensionAdditionAlternatives(Tokens =[{',',_}|_],Clist) ->
-    {ExtAddList,Rest2} = parse_ExtensionAdditionAlternativesList(Tokens,[]),
-    {Clist++lists:flatten(ExtAddList),Rest2};
-parse_ExtensionAdditionAlternatives(Tokens,Clist) ->
-    %% Empty
-    {Clist,Tokens}.
-
-parse_ExtensionAdditionAlternativesList([{',',_},Id = {identifier,_,_}|Rest],Acc) ->
-    {AlternativeType,Rest2} = parse_NamedType([Id|Rest]),
-    parse_ExtensionAdditionAlternativesList(Rest2,[AlternativeType|Acc]);
-parse_ExtensionAdditionAlternativesList([{',',_},C1 = {'[',_},C2 = {'[',_}|Rest],Acc) ->
-    {ExtAddGroup,Rest2} = parse_ExtensionAdditionAlternativesGroup([C1,C2|Rest],[]),
-    parse_ExtensionAdditionAlternativesList(Rest2,[ExtAddGroup|Acc]);
-parse_ExtensionAdditionAlternativesList(Tokens = [{'}',_}|_],Acc) ->
-    {lists:reverse(Acc),Tokens};
-parse_ExtensionAdditionAlternativesList(Tokens = [{',',_},{'...',_}|_],Acc) ->
-    {lists:reverse(Acc),Tokens};
-parse_ExtensionAdditionAlternativesList(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['}',', identifier']]}}).
-
-
-parse_ExtensionAdditionAlternativesGroup([ {'[',_},{'[',_},_VsnNr = {number,_,Num},{':',_}|Rest],[]) ->
-    parse_ExtensionAdditionAlternativesGroup2(Rest,Num);
-parse_ExtensionAdditionAlternativesGroup([ {'[',_},{'[',_}|Rest],[]) ->
-    parse_ExtensionAdditionAlternativesGroup2(Rest,undefined);
-parse_ExtensionAdditionAlternativesGroup(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['[[']]}}).
-
-
-parse_ExtensionAdditionAlternativesGroup2(Tokens,Num) ->
-    {CompTypeList,Rest} = parse_AlternativeTypeList(Tokens,[]),
-    case Rest of
-	[{']',_},{']',_}|Rest2] ->
-	    {[{'ExtensionAdditionGroup',Num}|CompTypeList] ++
-		['ExtensionAdditionGroupEnd'],Rest2};
+parse_ExtensionAdditionAlternativesList([{',',_}|Tokens1]=Tokens0, Acc) ->
+    try parse_ExtensionAdditionAlternative(Tokens1) of
+	{ExtAddAlt,Tokens2} ->
+	    parse_ExtensionAdditionAlternativesList(Tokens2, [ExtAddAlt|Acc])
+    catch
+	throw:{asn1_error,_} ->
+	    {lists:append(lists:reverse(Acc)),Tokens0}
+    end;
+parse_ExtensionAdditionAlternativesList(Tokens, Acc) ->
+    {lists:append(lists:reverse(Acc)),Tokens}.
+
+parse_ExtensionAdditionAlternative([#identifier{}|_]=Tokens0) ->
+    {NamedType,Tokens} = parse_NamedType(Tokens0),
+    {[NamedType],Tokens};
+parse_ExtensionAdditionAlternative([{'[',_},{'[',_}|Tokens0]) ->
+    Tokens2 = case Tokens0 of
+		  [{number,_,_},{':',_}|Tokens1] -> Tokens1;
+		  _ -> Tokens0
+	      end,
+    {GroupList,Tokens3} = parse_AlternativeTypeList(Tokens2),
+    case Tokens3 of
+	[{']',_},{']',_}|Tokens] ->
+	    {GroupList,Tokens};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,[']]']]}})
-    end.
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-%% parse_AlternativeTypeLists(Tokens,ExtensionDefault) ->
-%%     {AltTypeList,Rest1} = parse_AlternativeTypeList(Tokens),
-%%     {ExtensionAndException,Rest2} =
-%% 	case Rest1 of
-%% 	    [{',',_},{'...',L1},{'!',_}|Rest12] ->
-%% 		{_,Rest13} = parse_ExceptionIdentification(Rest12),
-%% 		%% Exception info is currently thrown away
-%% 		{[#'EXTENSIONMARK'{pos=L1}],Rest13};
-%% 	    [{',',_},{'...',L1}|Rest12] ->
-%% 		{[#'EXTENSIONMARK'{pos=L1}],Rest12};
-%% 	    _ ->
-%% 		{[],Rest1}
-%% 	end,
-%%     {AltTypeList2,Rest5} =
-%% 	case ExtensionAndException of
-%% 	    [] ->
-%% 		{AltTypeList,Rest2};
-%% 	    _ ->
-%% 		{ExtensionAddition,Rest3} =
-%% 		    case Rest2 of
-%% 			[{',',_}|Rest23] ->
-%% 			    parse_ExtensionAdditionAlternativeList(Rest23);
-%% 			_ ->
-%% 			    {[],Rest2}
-%% 		    end,
-%% 		{OptionalExtensionMarker,Rest4} =
-%% 		    case Rest3 of
-%% 			[{',',_},{'...',L3}|Rest31] ->
-%% 			    {[#'EXTENSIONMARK'{pos=L3}],Rest31};
-%% 			_ ->
-%% 			    {[],Rest3}
-%% 		    end,
-%% 		{AltTypeList ++ ExtensionAndException ++
-%% 		 ExtensionAddition ++ OptionalExtensionMarker, Rest4}
-%% 	end,
-%%     AltTypeList3 =
-%% 	case [X || X=#'EXTENSIONMARK'{} <- AltTypeList2] of
-%% 	    [] when ExtensionDefault == 'IMPLIED' ->
-%% 		AltTypeList2 ++ [#'EXTENSIONMARK'{}];
-%% 	    _ ->
-%% 		AltTypeList2
-%% 	end,
-%%     {AltTypeList3,Rest5}.
-    
-
-%% parse_AlternativeTypeList(Tokens) ->
-%%     parse_AlternativeTypeList(Tokens,[]).
-
-%% parse_AlternativeTypeList(Tokens,Acc) ->
-%%     {NamedType,Rest} = parse_NamedType(Tokens),
-%%     case Rest of
-%% 	[{',',_},Id = {identifier,_,_}|Rest2] ->
-%% 	    parse_AlternativeTypeList([Id|Rest2],[NamedType|Acc]);
-%% 	_ ->
-%% 	    {lists:reverse([NamedType|Acc]),Rest}
-%%     end.
+	    parse_error(Tokens3)
+    end;
+parse_ExtensionAdditionAlternative(Tokens) ->
+    parse_error(Tokens).
 
-    
+%%%
+%%% End of parsing of alternative type lists.
+%%%
 
-%% parse_ExtensionAdditionAlternativeList(Tokens) ->
-%%     parse_ExtensionAdditionAlternativeList(Tokens,[]).
-
-%% parse_ExtensionAdditionAlternativeList([{'[[',_}|Rest],Acc) ->
-%%     parse_ExtensionAdditionAlternativeList(Rest,Acc);
-%% parse_ExtensionAdditionAlternativeList(Tokens = [{identifier,_,_}|_Rest],Acc) ->
-%%     {Element,Rest0} = parse_NamedType(Tokens);
-%%     case Rest0 of
-%% 	[{',',_}|Rest01] ->
-%% 	    parse_ExtensionAdditionAlternativeList(Rest01,[Element|Acc]);
-%% 	_  ->
-%% 	    {lists:reverse([Element|Acc]),Rest0}
-%%     end.
-
-%% parse_ExtensionAdditionAlternatives([{'[[',_}|Rest]) ->
-%%     parse_ExtensionAdditionAlternatives(Rest,[]);
-%% parse_ExtensionAdditionAlternatives(Tokens) ->
-%%     throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-%% 		       [got,get_token(hd(Tokens)),expected,'[[']}}).
-
-%% parse_ExtensionAdditionAlternatives([Id = {identifier,_,_}|Rest],Acc) ->
-%%     {NamedType, Rest2} = parse_NamedType([Id|Rest]),
-%%     case Rest2 of
-%% 	[{',',_}|Rest21] ->
-%% 	    parse_ExtensionAdditionAlternatives(Rest21,[NamedType|Acc]);
-%% 	[{']]',_}|Rest21] ->
-%% 	    {lists:reverse(Acc),Rest21};
-%% 	_ ->
-%% 	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-%% 			       [got,get_token(hd(Rest2)),expected,[',',']]']]}})
-%%     end.
-
-parse_NamedType([{identifier,L1,Idname}|Rest]) ->
+parse_NamedType([#identifier{pos=L1,val=Idname}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {#'ComponentType'{pos=L1,name=Idname,typespec=Type,prop=mandatory},Rest2};
 parse_NamedType(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,identifier]}}).
+    parse_error(Tokens).
 
+%%%
+%%% Parse component type lists for SEQUENCE and SET.
+%%%
 
 parse_ComponentTypeLists(Tokens) ->
-    parse_ComponentTypeLists(Tokens,[]).
+    parse_ComponentTypeLists(Tokens, []).
 
-parse_ComponentTypeLists(Tokens = [{identifier,_,_}|_Rest0],Clist) ->
+parse_ComponentTypeLists([#identifier{}|_Rest0]=Tokens, Clist) ->
     {CompList,Rest1} = parse_ComponentTypeList(Tokens,[]),
     parse_ComponentTypeLists(Rest1,Clist++CompList);
-parse_ComponentTypeLists(Tokens = [{'COMPONENTS',_},{'OF',_}|_Rest],Clist) ->
-    {CompList,Rest1} = parse_ComponentTypeList(Tokens,[]),
-    parse_ComponentTypeLists(Rest1,Clist++CompList);
-parse_ComponentTypeLists([{'...',L1},{'!',_}|Rest02],Clist0) ->
-    {_,Rest03} = parse_ExceptionIdentification(Rest02),
-    %% Exception info is currently thrown away
-    parse_ComponentTypeLists2(Rest03,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
+parse_ComponentTypeLists([{'COMPONENTS',_},{'OF',_}|_]=Tokens,Clist) ->
+    {CompList,Rest1} = parse_ComponentTypeList(Tokens, []),
+    parse_ComponentTypeLists(Rest1, Clist++CompList);
 parse_ComponentTypeLists([{',',L1},{'...',_},{'!',_}|Rest02],Clist0) when Clist0 =/= []->
     {_,Rest03} = parse_ExceptionIdentification(Rest02),
     %% Exception info is currently thrown away
     parse_ComponentTypeLists2(Rest03,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
-
- parse_ComponentTypeLists([{',',_},{'...',L1}|Rest02],Clist0) when Clist0 =/= []->
+parse_ComponentTypeLists([{',',_},{'...',L1}|Rest02],Clist0) when Clist0 =/= []->
     parse_ComponentTypeLists2(Rest02,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
 parse_ComponentTypeLists([{'...',L1}|Rest02],Clist0) ->
     parse_ComponentTypeLists2(Rest02,Clist0++[#'EXTENSIONMARK'{pos=L1}]);
 parse_ComponentTypeLists(Tokens = [{'}',_L1}|_Rest02],Clist0) ->
     {Clist0,Tokens};
 parse_ComponentTypeLists(Tokens, _) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			identifier]}}).
+    parse_error(Tokens).
 
 parse_ComponentTypeLists2(Tokens,Clist) ->
     {ExtAdd,Rest} = parse_ExtensionAdditions(Tokens,Clist),
@@ -2358,12 +1841,12 @@ parse_OptionalExtensionMarker(Tokens,Clist) ->
     {Clist,Tokens}.
 
 
-parse_ComponentTypeList([{',',_},Id = {identifier,_,_}|Rest],Acc) when Acc =/= [] ->
-    {ComponentType,Rest2} = parse_ComponentType([Id|Rest]),
-    parse_ComponentTypeList(Rest2,[ComponentType|Acc]);
-parse_ComponentTypeList([{',',_},C1={'COMPONENTS',_},C2={'OF',_}|Rest],Acc) when Acc =/= [] ->
-    {ComponentType,Rest2} = parse_ComponentType([C1,C2|Rest]),
-    parse_ComponentTypeList(Rest2,[ComponentType|Acc]);
+parse_ComponentTypeList([{',',_}|[#identifier{}|_]=Tokens0], Acc) when Acc =/= [] ->
+    {ComponentType,Tokens} = parse_ComponentType(Tokens0),
+    parse_ComponentTypeList(Tokens, [ComponentType|Acc]);
+parse_ComponentTypeList([{',',_}|[{'COMPONENTS',_},{'OF',_}|_]=Tokens0], Acc) when Acc =/= [] ->
+    {ComponentType,Tokens} = parse_ComponentType(Tokens0),
+    parse_ComponentTypeList(Tokens, [ComponentType|Acc]);
 parse_ComponentTypeList(Tokens = [{'}',_}|_],Acc) ->
     {lists:reverse(Acc),Tokens};
 parse_ComponentTypeList(Tokens = [{']',_},{']',_}|_],Acc) ->
@@ -2374,10 +1857,7 @@ parse_ComponentTypeList(Tokens,[]) ->
     {ComponentType,Rest} = parse_ComponentType(Tokens),
     parse_ComponentTypeList(Rest,[ComponentType]);
 parse_ComponentTypeList(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['}',', identifier']]}}).
+    parse_error(Tokens).
 
 parse_ExtensionAdditions(Tokens=[{',',_}|_],Clist) ->
     {ExtAddList,Rest2} = parse_ExtensionAdditionList(Tokens,[]),
@@ -2386,46 +1866,36 @@ parse_ExtensionAdditions(Tokens,Clist) ->
     %% Empty
     {Clist,Tokens}.
 
-parse_ExtensionAdditionList([{',',_},Id = {identifier,_,_}|Rest],Acc) ->
-    {ComponentType,Rest2} = parse_ComponentType([Id|Rest]),
-    parse_ExtensionAdditionList(Rest2,[ComponentType|Acc]);
-parse_ExtensionAdditionList([{',',_},C1={'COMPONENTS',_},C2={'OF',_}|Rest],Acc) ->
-    {ComponentType,Rest2} = parse_ComponentType([C1,C2|Rest]),
-    parse_ExtensionAdditionList(Rest2,[ComponentType|Acc]);
-parse_ExtensionAdditionList([{',',_},C1 = {'[',_},C2 = {'[',_}|Rest],Acc) ->
-    {ExtAddGroup,Rest2} = parse_ExtensionAdditionGroup([C1,C2|Rest],[]),
+parse_ExtensionAdditionList([{',',_}|[#identifier{}|_]=Tokens0], Acc) ->
+    {ComponentType,Tokens} = parse_ComponentType(Tokens0),
+    parse_ExtensionAdditionList(Tokens, [ComponentType|Acc]);
+parse_ExtensionAdditionList([{',',_}|[{'COMPONENTS',_},{'OF',_}|_]=Tokens0], Acc) ->
+    {ComponentType,Tokens} = parse_ComponentType(Tokens0),
+    parse_ExtensionAdditionList(Tokens, [ComponentType|Acc]);
+parse_ExtensionAdditionList([{',',_},{'[',_},{'[',_}|Tokens], Acc) ->
+    {ExtAddGroup,Rest2} = parse_ExtensionAdditionGroup(Tokens),
     parse_ExtensionAdditionList(Rest2,[ExtAddGroup|Acc]);
-parse_ExtensionAdditionList(Tokens = [{'}',_}|_],Acc) ->
+parse_ExtensionAdditionList([{'}',_}|_]=Tokens, Acc) ->
     {lists:reverse(Acc),Tokens};
-parse_ExtensionAdditionList(Tokens = [{',',_},{'...',_}|_],Acc) ->
+parse_ExtensionAdditionList([{',',_},{'...',_}|_]=Tokens, Acc) ->
     {lists:reverse(Acc),Tokens};
-parse_ExtensionAdditionList(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['}',', identifier']]}}).
-
+parse_ExtensionAdditionList(Tokens, _) ->
+    parse_error(Tokens).
 
-parse_ExtensionAdditionGroup([ {'[',_},{'[',_},_VsnNr = {number,_,Num},{':',_}|Rest],[]) ->
-    parse_ExtensionAdditionGroup2(Rest,Num);
-parse_ExtensionAdditionGroup([ {'[',_},{'[',_}|Rest],[]) ->
-    parse_ExtensionAdditionGroup2(Rest,undefined);
-parse_ExtensionAdditionGroup(Tokens,_) ->
-    throw({asn1_error,
-	   {get_line(hd(Tokens)),get(asn1_module),
-	    [got,[get_token(hd(Tokens)),get_token(hd(tl(Tokens)))],
-	     expected,['[[']]}}).
 
+parse_ExtensionAdditionGroup([{number,_,Num},{':',_}|Tokens]) ->
+    parse_ExtensionAdditionGroup2(Tokens, Num);
+parse_ExtensionAdditionGroup(Tokens) ->
+    parse_ExtensionAdditionGroup2(Tokens, undefined).
 
-parse_ExtensionAdditionGroup2(Tokens,Num) ->
+parse_ExtensionAdditionGroup2(Tokens, Num) ->
     {CompTypeList,Rest} = parse_ComponentTypeList(Tokens,[]),
     case Rest of
 	[{']',_},{']',_}|Rest2] ->
 	    {[{'ExtensionAdditionGroup',Num}|CompTypeList] ++
 		['ExtensionAdditionGroupEnd'],Rest2};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,[']]']]}})
+	    parse_error(Rest)
     end.
 
 
@@ -2444,79 +1914,81 @@ parse_ComponentType(Tokens) ->
 	    Result
     end.
 
-	    
-
-parse_SignedNumber([{number,_,Value}|Rest]) ->
-    {Value,Rest};
-parse_SignedNumber([{'-',_},{number,_,Value}|Rest]) ->
-    {-Value,Rest};
-parse_SignedNumber(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,
-			[number,'-number']]}}).
-
-parse_Enumerations(Tokens=[{identifier,_,_}|_Rest],ExtensionDefault) ->
-    parse_Enumerations(Tokens,[],ExtensionDefault);
-parse_Enumerations([H|_T],_) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,identifier]}}).
-
-parse_Enumerations(Tokens = [{identifier,_,_},{'(',_}|_Rest], Acc, ExtensionDefault) ->
-    {NamedNumber,Rest2} = parse_NamedNumber(Tokens),
-    case Rest2 of
-	[{',',_}|Rest3] ->
-	    parse_Enumerations(Rest3,[NamedNumber|Acc], ExtensionDefault);
-	_ when ExtensionDefault == 'IMPLIED'->
-	    {lists:reverse(['EXTENSIONMARK',NamedNumber|Acc]),Rest2};
-	_ ->
-	    {lists:reverse([NamedNumber|Acc]),Rest2}
-    end;
-parse_Enumerations([{identifier,_,Id}|Rest], Acc, ExtensionDefault) ->
-    case Rest of
-	[{',',_}|Rest2] ->
-	    parse_Enumerations(Rest2,[Id|Acc], ExtensionDefault);
-	_ when ExtensionDefault == 'IMPLIED' ->
-	    {lists:reverse(['EXTENSIONMARK', Id |Acc]),Rest};
+%%%
+%%% Parse ENUMERATED.
+%%%
+
+parse_Enumerations(Tokens0) ->
+    {Root,Tokens1} = parse_Enumeration(Tokens0),
+    case Tokens1 of
+	[{',',_},{'...',_},{',',_}|Tokens2] ->
+	    {Ext,Tokens} = parse_Enumeration(Tokens2),
+	    {Root++['EXTENSIONMARK'|Ext],Tokens};
+	[{',',_},{'...',_}|Tokens] ->
+	    {Root++['EXTENSIONMARK'],Tokens};
 	_ ->
-	    {lists:reverse([Id|Acc]),Rest}
-    end;
-parse_Enumerations([{'...',_}|Rest], Acc, _ExtensionDefault) ->
-    case Rest of
-	[{',',_}|Rest2] ->
-	    parse_Enumerations(Rest2,['EXTENSIONMARK'|Acc],undefined);
-	_ ->
-	    {lists:reverse(['EXTENSIONMARK'|Acc]),Rest}
+	    case get(extensiondefault) of
+		'IMPLIED' ->
+		    {Root++['EXTENSIONMARK'],Tokens1};
+		_ ->
+		    {Root,Tokens1}
+	    end
+    end.
+
+parse_Enumeration(Tokens0) ->
+    {Item,Tokens} = parse_EnumerationItem(Tokens0),
+    parse_Enumeration_1(Tokens, [Item]).
+
+parse_Enumeration_1([{',',_}|Tokens1]=Tokens0, Acc) ->
+    try parse_EnumerationItem(Tokens1) of
+	{Item,Tokens} ->
+	    parse_Enumeration_1(Tokens, [Item|Acc])
+    catch
+	throw:{asn1_error,_} ->
+	    {lists:reverse(Acc),Tokens0}
     end;
-parse_Enumerations([H|_T],_,_) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,identifier]}}).
+parse_Enumeration_1(Tokens, Acc) ->
+    {lists:reverse(Acc),Tokens}.
+
+parse_EnumerationItem([#identifier{},{'(',_}|_]=Tokens) ->
+    parse_NamedNumber(Tokens);
+parse_EnumerationItem([#identifier{val=Id}|Tokens]) ->
+    {Id,Tokens};
+parse_EnumerationItem(Tokens) ->
+    parse_error(Tokens).
+
+%%%
+%%% End of parsing of ENUMERATED.
+%%%
 
 parse_NamedNumberList(Tokens) ->
-    parse_NamedNumberList(Tokens,[]).
+    parse_NamedNumberList(Tokens, []).
 
-parse_NamedNumberList(Tokens,Acc) ->
+parse_NamedNumberList(Tokens, Acc) ->
     {NamedNum,Rest} = parse_NamedNumber(Tokens),
     case Rest of
 	[{',',_}|Rest2] ->
 	    parse_NamedNumberList(Rest2,[NamedNum|Acc]);
 	_ ->
-	    {lists:reverse([NamedNum|Acc]),Rest}
+	    {lists:reverse(Acc, [NamedNum]),Rest}
     end.
 
-parse_NamedNumber([{identifier,_,Name},{'(',_}|Rest]) ->
+parse_NamedNumber([#identifier{val=Name},{'(',_}|Rest]) ->
     Flist = [fun parse_SignedNumber/1,
 	     fun parse_DefinedValue/1],
     case parse_or(Rest, Flist) of
 	{NamedNum,[{')',_}|Rest2]} ->
 	    {{'NamedNumber',Name,NamedNum},Rest2};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,'NamedNumberList']}})
+	    parse_error(Rest)
     end;
 parse_NamedNumber(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,identifier]}}).
+    parse_error(Tokens).
 
+parse_SignedNumber([{number,_,Value}|Rest]) ->
+    {Value,Rest};
+parse_SignedNumber(Tokens) ->
+    parse_error(Tokens).
 
 parse_Tag([{'[',_}|Rest]) ->
     {Class,Rest2} = parse_Class(Rest),
@@ -2531,12 +2003,8 @@ parse_Tag([{'[',_}|Rest]) ->
 	[{']',_}|Rest4] ->
 	    {#tag{class=Class,number=ClassNumber},Rest4};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest3)),get(asn1_module),
-			       [got,get_token(hd(Rest3)),expected,']']}})
-    end;
-parse_Tag(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'[']}}).
+	    parse_error(Rest3)
+    end.
 
 parse_Class([{'UNIVERSAL',_}|Rest]) ->
     {'UNIVERSAL',Rest};
@@ -2569,10 +2037,10 @@ parse_BuiltinValue(Tokens = [{'{',_}|_Rest]) ->
 	     fun parse_SequenceValue/1, 
 	     fun parse_ObjectIdentifierValue/1],
     parse_or(Tokens, Flist);
-parse_BuiltinValue([{identifier,_,IdName},{':',_}|Rest]) ->
+parse_BuiltinValue([#identifier{val=IdName},{':',_}|Rest]) ->
     {Value,Rest2} = parse_Value(Rest),
     {{'CHOICE',{IdName,Value}},Rest2};
-parse_BuiltinValue(Tokens=[{'NULL',_},{':',_}|_Rest])  ->
+parse_BuiltinValue([{'NULL',_},{':',_}|_]=Tokens)  ->
     parse_ObjectClassFieldValue(Tokens);
 parse_BuiltinValue([{'NULL',_}|Rest])  ->
     {'NULL',Rest};
@@ -2588,31 +2056,29 @@ parse_BuiltinValue([{cstring,_,Cstr}|Rest]) ->
     {Cstr,Rest};
 parse_BuiltinValue([{number,_,Num}|Rest]) ->
     {Num,Rest};
-parse_BuiltinValue([{'-',_},{number,_,Num}|Rest]) ->
-    {- Num,Rest};
 parse_BuiltinValue(Tokens) ->
     parse_ObjectClassFieldValue(Tokens).
 
-parse_DefinedValue(Tokens=[{identifier,_,_},{'{',_}|_Rest]) ->
-    parse_ParameterizedValue(Tokens);
-%% Externalvaluereference
-parse_DefinedValue([{typereference,L1,Tname},{'.',_},{identifier,_,Idname}|Rest]) ->
+parse_DefinedValue(Tokens) ->
+    Flist = [fun parse_ParameterizedValue/1,
+	     fun parse_DefinedValue2/1],
+    parse_or(Tokens, Flist).
+
+parse_DefinedValue2([{typereference,L1,Tname},
+		     {'.',_},
+		     #identifier{val=Idname}|Rest]) ->
     {#'Externalvaluereference'{pos=L1,module=Tname,value=Idname},Rest};
 %% valuereference
-parse_DefinedValue([Id = {identifier,_,_}|Rest]) ->
+parse_DefinedValue2([#identifier{}=Id|Rest]) ->
     {identifier2Extvalueref(Id),Rest};
-%% ParameterizedValue
-parse_DefinedValue(Tokens) ->
-    parse_ParameterizedValue(Tokens).
+parse_DefinedValue2(Tokens) ->
+    parse_error(Tokens).
 
 
 parse_SequenceValue([{'{',_}|Tokens]) ->
-    parse_SequenceValue(Tokens,[]);
-parse_SequenceValue(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_SequenceValue(Tokens, []).
 
-parse_SequenceValue([{identifier,Pos,IdName}|Rest],Acc) ->
+parse_SequenceValue([#identifier{pos=Pos,val=IdName}|Rest],Acc) ->
     {Value,Rest2} = parse_Value(Rest),
     SeqTag = #seqtag{pos=Pos,module=get(asn1_module),val=IdName},
     case Rest2 of
@@ -2621,18 +2087,13 @@ parse_SequenceValue([{identifier,Pos,IdName}|Rest],Acc) ->
 	[{'}',_}|Rest3] ->
 	    {lists:reverse(Acc, [{SeqTag,Value}]),Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end;
 parse_SequenceValue(Tokens,_Acc) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,identifier]}}).
+    parse_error(Tokens).
 
 parse_SequenceOfValue([{'{',_}|Tokens]) ->
-    parse_SequenceOfValue(Tokens,[]);
-parse_SequenceOfValue(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_SequenceOfValue(Tokens, []).
 
 parse_SequenceOfValue(Tokens,Acc) ->
     {Value,Rest2} = parse_Value(Tokens),
@@ -2640,10 +2101,9 @@ parse_SequenceOfValue(Tokens,Acc) ->
 	[{',',_}|Rest3] ->
 	    parse_SequenceOfValue(Rest3,[Value|Acc]);
 	[{'}',_}|Rest3] ->
-	    {lists:reverse([Value|Acc]),Rest3};
+	    {lists:reverse(Acc, [Value]),Rest3};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'}']}})
+	    parse_error(Rest2)
     end.
 
 parse_ValueSetTypeAssignment([{typereference,L1,Name}|Rest]) ->
@@ -2653,29 +2113,22 @@ parse_ValueSetTypeAssignment([{typereference,L1,Name}|Rest]) ->
 	    {ValueSet,Rest4} = parse_ValueSet(Rest3),
 	    {#valuedef{pos=L1,name=Name,type=Type,value=ValueSet,
 		       module=get(asn1_module)},Rest4};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(L1),get(asn1_module),
-			       [got,get_token(H),expected,'::=']}})
-    end;
-parse_ValueSetTypeAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,
-				   typereference]}}).
+	_ ->
+	    parse_error(Rest2)
+    end.
 
 parse_ValueSet([{'{',_}|Rest]) ->
     {Elems,Rest2} = parse_ElementSetSpecs(Rest),
     case Rest2 of
 	[{'}',_}|Rest3] ->
 	    {{valueset,Elems},Rest3};
-	[H|_T] ->
-	    throw({asn1_error,{get_line(H),get(asn1_module),
-			       [got,get_token(H),expected,'}']}})
+	_ ->
+	    parse_error(Rest2)
     end;
 parse_ValueSet(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'{']}}).
+    parse_error(Tokens).
 
-parse_ValueAssignment([{identifier,L1,IdName}|Rest]) ->
+parse_ValueAssignment([#identifier{pos=L1,val=IdName}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     case Rest2 of
 	[{'::=',_}|Rest3] ->
@@ -2684,12 +2137,8 @@ parse_ValueAssignment([{identifier,L1,IdName}|Rest]) ->
 	    {#valuedef{pos=L1,name=IdName,type=Type,value=Value,
 		       module=get(asn1_module)},Rest4};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest2)),get(asn1_module),
-			       [got,get_token(hd(Rest2)),expected,'::=']}})
-    end;
-parse_ValueAssignment(Tokens) ->
-    throw({asn1_assignment_error,{get_line(hd(Tokens)),get(asn1_module),
-				  [got,get_token(hd(Tokens)),expected,identifier]}}).
+	    parse_error(Rest2)
+    end.
 
 %% SizeConstraint
 parse_SubtypeElements([{'SIZE',_}|Tokens]) ->
@@ -2709,8 +2158,7 @@ parse_SubtypeElements([{'WITH',_},{'COMPONENTS',_},{'{',_},{'...',_},{',',_}|Tok
 	[{'}',_}|Rest2] ->
 	    {{'WITH COMPONENTS',{'PartialSpecification',Constraint}},Rest2};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,'}']}})
+	    parse_error(Rest)
     end;
 parse_SubtypeElements([{'WITH',_},{'COMPONENTS',_},{'{',_}|Tokens]) ->
     {Constraint,Rest} = parse_TypeConstraints(Tokens),
@@ -2718,17 +2166,11 @@ parse_SubtypeElements([{'WITH',_},{'COMPONENTS',_},{'{',_}|Tokens]) ->
 	[{'}',_}|Rest2] ->
 	    {{'WITH COMPONENTS',{'FullSpecification',Constraint}},Rest2};
 	_ ->
-	    throw({asn1_error,{get_line(hd(Rest)),get(asn1_module),
-			       [got,get_token(hd(Rest)),expected,'}']}})
+	    parse_error(Rest)
     end;
 parse_SubtypeElements([{'PATTERN',_}|Tokens]) ->
     {Value,Rest} = parse_Value(Tokens),
     {{pattern,Value},Rest};
-%% SingleValue
-%% ContainedSubtype
-%% ValueRange
-%% TypeConstraint
-%% Moved fun parse_Value/1 and fun parse_Type/1 to parse_Elements
 parse_SubtypeElements(Tokens) ->
     Flist = [fun parse_ContainedSubtype/1,
 	     fun parse_Value/1, 
@@ -2753,10 +2195,7 @@ parse_ContainedSubtype([{'INCLUDES',_}|Rest]) ->
     {Type,Rest2} = parse_Type(Rest),
     {{'ContainedSubtype',Type},Rest2};
 parse_ContainedSubtype(Tokens) ->
-    throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
-		       [got,get_token(hd(Tokens)),expected,'INCLUDES']}}).
-%%parse_ContainedSubtype(Tokens) -> %this option is moved to parse_SubtypeElements
-%%    parse_Type(Tokens).
+    parse_error(Tokens).
 
 parse_UpperEndpoint([{'<',_}|Rest]) ->
     parse_UpperEndpoint(lt,Rest);
@@ -2775,30 +2214,27 @@ parse_UpperEndpoint(Lt,Tokens) ->
 
 parse_MIN([{'MIN',_}|T]) ->
     {'MIN',T};
-parse_MIN([H|_]) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,'MIN']}}).
+parse_MIN(Tokens) ->
+    parse_error(Tokens).
 
 parse_MAX([{'MAX',_}|T]) ->
     {'MAX',T};
-parse_MAX([H|_]) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,'MAX']}}).
+parse_MAX(Tokens) ->
+    parse_error(Tokens).
 
 parse_TypeConstraints(Tokens) ->
-    parse_TypeConstraints(Tokens,[]).
+    parse_TypeConstraints(Tokens, []).
 
-parse_TypeConstraints([{identifier,_,_}|Rest],Acc) ->
+parse_TypeConstraints([#identifier{}|Rest], Acc) ->
     {ComponentConstraint,Rest2} = parse_ComponentConstraint(Rest),
     case Rest2 of
 	[{',',_}|Rest3] ->
-	    parse_TypeConstraints(Rest3,[ComponentConstraint|Acc]);
+	    parse_TypeConstraints(Rest3, [ComponentConstraint|Acc]);
 	_ ->
-	    {lists:reverse([ComponentConstraint|Acc]),Rest2}
+	    {lists:reverse(Acc, [ComponentConstraint]),Rest2}
     end;
-parse_TypeConstraints([H|_T],_) ->
-    throw({asn1_error,{get_line(H),get(asn1_module),
-		       [got,get_token(H),expected,identifier]}}).
+parse_TypeConstraints(Tokens, _) ->
+    parse_error(Tokens).
 
 parse_ComponentConstraint(Tokens = [{'(',_}|_Rest]) ->
     {ValueConstraint,Rest2} = parse_Constraint(Tokens),
@@ -2836,56 +2272,18 @@ merge_constraints([], Cacc, Eacc) ->
 get_line({Token,Pos,_}) when is_integer(Pos), is_atom(Token) ->
     Pos;
 get_line({Token,Pos}) when is_integer(Pos),is_atom(Token) ->
-    Pos;
-get_line(_) ->
-    undefined.
-
-get_token({_,Pos,Token}) when is_integer(Pos),is_atom(Token) ->
-    Token;
+    Pos.
+
+get_token({valuefieldreference,_,FieldName}) ->
+    list_to_atom([$&|atom_to_list(FieldName)]);
+get_token({typefieldreference,_,FieldName}) ->
+    list_to_atom([$&|atom_to_list(FieldName)]);
+get_token({Token,Pos,Value}) when is_integer(Pos), is_atom(Token) ->
+    Value;
 get_token({'$end',Pos}) when is_integer(Pos) ->
-    undefined;
+    'END-OF-FILE';
 get_token({Token,Pos}) when is_integer(Pos),is_atom(Token) ->
-    Token;
-get_token(_) ->
-    undefined.
-
-%% Choose the "best" error:
-%% 1) the error with the highest line number,
-%% 2) the last error which is not an asn1_assignment_error, or
-%% 3) the last error.
-prioritize_error([_|_]=ErrList) ->
-    case lists:keymember(asn1_error,1,ErrList) of
-	false -> % only asn1_assignment_error -> take the last
-	    lists:last(ErrList);
-	true -> % contains errors from deeper in a Type
-	    NewErrList = [_Err={_,_}|_RestErr] =
-		lists:filter(fun({asn1_error,_})->true;(_)->false end,
-			     ErrList),
-	    SplitErrs =
-		lists:splitwith(fun({_,X})->
-					case element(1,X) of
-					    Int when is_integer(Int) -> true;
-					    _ -> false
-					end
-				end,
-				NewErrList),
-	    case SplitErrs of
-		{[],UndefPosErrs} -> % if no error with Positon exists
-		    lists:last(UndefPosErrs);
-		{IntPosErrs,_} ->
-		    IntPosReasons = lists:map(fun(X)->element(2,X) end,IntPosErrs),
-		    SortedReasons = lists:keysort(1,IntPosReasons),
-		    {asn1_error,lists:last(SortedReasons)}
-	    end
-    end.
-
-%% most_prio_error([H={_,Reason}|T],Atom,Err) when is_atom(Atom) ->
-%%     most_prio_error(T,element(1,Reason),H);
-%% most_prio_error([H={_,Reason}|T],Greatest,Err) ->
-%%     case element(1,Reason) of
-%% 	Pos when is_integer(Pos),Pos>Greatest ->
-%% 	    most_prio_error(
-
+    Token.
 
 tref2Exttref(#typereference{pos=Pos,val=Name}) ->
     #'Externaltypereference'{pos=Pos,
@@ -2910,3 +2308,6 @@ lookahead_assignment([{'END',_}|_Rest]) ->
 lookahead_assignment(Tokens) ->
     {_,_} = parse_Assignment(Tokens),
     ok.
+
+parse_error(Tokens) ->
+    throw({asn1_error,{parse_error,Tokens}}).
diff --git a/lib/asn1/test/Makefile b/lib/asn1/test/Makefile
index edfdc7f2f4..7bd4750c52 100644
--- a/lib/asn1/test/Makefile
+++ b/lib/asn1/test/Makefile
@@ -110,11 +110,13 @@ MODULES= \
 	testValueTest \
 	testUniqueObjectSets \
 	testRfcs \
+	testImporting \
 	asn1_test_lib \
 	asn1_app_test \
 	asn1_appup_test \
 	asn1_SUITE \
-	error_SUITE
+	error_SUITE \
+	syntax_SUITE
 
 ERL_FILES= $(MODULES:%=%.erl)
 
diff --git a/lib/asn1/test/asn1_SUITE.erl b/lib/asn1/test/asn1_SUITE.erl
index 8013dd5605..5e8da14fdf 100644
--- a/lib/asn1/test/asn1_SUITE.erl
+++ b/lib/asn1/test/asn1_SUITE.erl
@@ -52,8 +52,7 @@ all() ->
 groups() ->
     Parallel = asn1_test_lib:parallel(),
     [{compile, Parallel,
-      [c_syntax,
-       c_string,
+      [c_string,
        constraint_equivalence]},
 
      {ber, Parallel,
@@ -563,24 +562,6 @@ testSetOfCho(Config, Rule, Opts) ->
     asn1_test_lib:compile("SetOfCho", Config, [Rule|Opts]),
     testSetOfCho:main(Rule).
 
-c_syntax(Config) ->
-    DataDir = ?config(data_dir, Config),
-    [{error, _} = asn1ct:compile(filename:join(DataDir, F))
-     || F <-["Syntax",
-             "BadTypeEnding",
-             "BadValueAssignment1",
-             "BadValueAssignment2",
-             "BadValueSet",
-             "ChoiceBadExtension",
-             "EnumerationBadExtension",
-             "Example",
-             "Export1",
-             "MissingEnd",
-             "SequenceBadComma",
-             "SequenceBadComponentName",
-             "SequenceBadComponentType",
-             "SeqBadComma"]].
-
 c_string(Config) ->
     test(Config, fun c_string/3).
 c_string(Config, Rule, Opts) ->
@@ -819,9 +800,11 @@ testDeepTConstr(Config, Rule, Opts) ->
 testImport(Config) ->
     test(Config, fun testImport/3).
 testImport(Config, Rule, Opts) ->
-    Files = ["ImportsFrom","ImportsFrom2","ImportsFrom3"],
+    Files = ["ImportsFrom","ImportsFrom2","ImportsFrom3",
+	     "Importing","Exporting"],
     asn1_test_lib:compile_all(Files, Config, [Rule|Opts]),
     42 = 'ImportsFrom':i(),
+    testImporting:main(),
     ok.
 
 testMegaco(Config) -> test(Config, fun testMegaco/3).
@@ -1095,6 +1078,7 @@ test_modules() ->
      "CommonDataTypes",
      "Constraints",
      "ContextSwitchingTypes",
+     "CoverParser",
      "DS-EquipmentUser-CommonFunctionOrig-TransmissionPath",
      "Enum",
      "From",
diff --git a/lib/asn1/test/asn1_SUITE_data/BadTypeEnding.asn b/lib/asn1/test/asn1_SUITE_data/BadTypeEnding.asn
deleted file mode 100644
index 3ccd838ac0..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/BadTypeEnding.asn
+++ /dev/null
@@ -1,6 +0,0 @@
-BadTypeEnding  DEFINITIONS ::=
-BEGIN
-
-T ::= Typ;
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/BadValueAssignment1.asn1 b/lib/asn1/test/asn1_SUITE_data/BadValueAssignment1.asn1
deleted file mode 100644
index a5d4984e60..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/BadValueAssignment1.asn1
+++ /dev/null
@@ -1,8 +0,0 @@
-BadValueAssignment1  DEFINITIONS ::=
-BEGIN
-
-int INTEGER ::= 3
-
-int2 integer ::= 3
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/BadValueAssignment2.asn1 b/lib/asn1/test/asn1_SUITE_data/BadValueAssignment2.asn1
deleted file mode 100644
index 7a96406001..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/BadValueAssignment2.asn1
+++ /dev/null
@@ -1,8 +0,0 @@
-BadValueAssignment2  DEFINITIONS ::=
-BEGIN
-
-int INTEGER ::= 3
-
-int2 ::= 3
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/BadValueSet.asn1 b/lib/asn1/test/asn1_SUITE_data/BadValueSet.asn1
deleted file mode 100644
index 68bd4380b7..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/BadValueSet.asn1
+++ /dev/null
@@ -1,9 +0,0 @@
-BadValueSet  DEFINITIONS ::=
-BEGIN
-
-Int INTEGER ::= {1|2|3}
-
-Int2 INTEGER ::= {
-    1,2,3}
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/ChoExtension.asn1 b/lib/asn1/test/asn1_SUITE_data/ChoExtension.asn1
index f6fe18be10..18473bae30 100644
--- a/lib/asn1/test/asn1_SUITE_data/ChoExtension.asn1
+++ b/lib/asn1/test/asn1_SUITE_data/ChoExtension.asn1
@@ -41,10 +41,4 @@ ChoExt4 ::= CHOICE
   str OCTET STRING
 }
 
-ChoEmptyRoot ::= CHOICE {
-  ...,
-  bool BOOLEAN,
-  int INTEGER (0..7)
-}
-
 END
diff --git a/lib/asn1/test/asn1_SUITE_data/ChoiceBadExtension.asn1 b/lib/asn1/test/asn1_SUITE_data/ChoiceBadExtension.asn1
deleted file mode 100644
index d0789d7414..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/ChoiceBadExtension.asn1
+++ /dev/null
@@ -1,27 +0,0 @@
-ChoiceBadExtension DEFINITIONS ::=
-BEGIN
-
-Seq ::= SEQUENCE {
-    ...,
-    name PrintableString,
-    location INTEGER {home(0),field(1),roving(2)},
-    age INTEGER 
-    }
-
-Cho1 ::= CHOICE {
-    name PrintableString,
-    ...,
-    location INTEGER {home(0),field(1),roving(2)},
-    age INTEGER 
-    }
-
-Cho2 ::= CHOICE {
-    ...,
-    name PrintableString,
-    location INTEGER {home(0),field(1),roving(2)},
-    age INTEGER 
-    }
-
-END
-
-
diff --git a/lib/asn1/test/asn1_SUITE_data/CoverParser.asn1 b/lib/asn1/test/asn1_SUITE_data/CoverParser.asn1
new file mode 100644
index 0000000000..75d40188ca
--- /dev/null
+++ b/lib/asn1/test/asn1_SUITE_data/CoverParser.asn1
@@ -0,0 +1,57 @@
+CoverParser DEFINITIONS AUTOMATIC TAGS ::=
+BEGIN
+
+ Cho1 ::= CHOICE {
+   i INTEGER,
+   ... ! 42,
+   [[ b BOOLEAN ]]
+ }
+
+ Cho2 ::= CHOICE {
+   i INTEGER,
+   ...,
+   [[ b BOOLEAN,
+      s IA5String ]],
+   ...
+ }
+
+ Int1 ::= INTEGER (CONSTRAINED BY {INTEGER:1,INTEGER:2})
+
+ Seq1 ::= SEQUENCE {
+   ... ! INTEGER:1
+ }
+
+ Seq2 ::= SEQUENCE {
+   ... ! INTEGER:1,
+   i INTEGER
+ }
+
+ Seq3 ::= SEQUENCE {
+   b BOOLEAN,
+   ... ! INTEGER:1,
+   i INTEGER
+ }
+
+ Seq4 ::= SEQUENCE {
+   a INTEGER OPTIONAL,
+   b OCTET STRING OPTIONAL
+ } (WITH COMPONENTS {a ABSENT, b OPTIONAL} |
+    WITH COMPONENTS {a PRESENT, b PRESENT})
+
+ SeqOf1 ::= SEQUENCE OF INTEGER
+ SeqOf2 ::= SeqOf1 (WITH COMPONENT (0..7))
+
+ SegOf3 ::= SEQUENCE (SIZE (1..10)) OF id INTEGER
+
+ Set1 ::= SET {
+   ... ! INTEGER:1
+ }
+
+ Set2 ::= SET {
+   ... ! INTEGER:1,
+   a INTEGER
+ }
+
+ SetOf3 ::= SET (SIZE (1..10)) OF id INTEGER
+
+END
diff --git a/lib/asn1/test/asn1_SUITE_data/Example.asn1 b/lib/asn1/test/asn1_SUITE_data/Example.asn1
deleted file mode 100644
index 2639f63940..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/Example.asn1
+++ /dev/null
@@ -1,20 +0,0 @@
-Example  DEFINITIONS ::=
-BEGIN
-
-T ::= Typ
-
-Typ ::= SEQUENCE {
-    a b,
-    c Typ}
---ECLASS ::= CLASS {
---    &num       INTEGER UNIQUE,
---    &Typo
---    } WITH SYNTAX {
---    &Typo DETERMINED BY &num
---    }
-
---v1 ECLASS ::= {INTEGER DETERMINED BY 12}
-
---v2 INTEGER ::= 13
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/Export1.asn b/lib/asn1/test/asn1_SUITE_data/Export1.asn
deleted file mode 100644
index 78ead8f4d2..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/Export1.asn
+++ /dev/null
@@ -1,7 +0,0 @@
-Export1  DEFINITIONS ::=
-BEGIN
-EXPORTS T
-
-T ::= Typ	
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/Exporting.asn1 b/lib/asn1/test/asn1_SUITE_data/Exporting.asn1
new file mode 100644
index 0000000000..e4f32f6788
--- /dev/null
+++ b/lib/asn1/test/asn1_SUITE_data/Exporting.asn1
@@ -0,0 +1,18 @@
+Exporting DEFINITIONS AUTOMATIC TAGS ::=
+BEGIN
+
+  Seq ::= SEQUENCE { id INTEGER, f BOOLEAN }
+  PtSeq{T} ::= SEQUENCE { a T }
+
+  CL ::= CLASS {
+     &id INTEGER UNIQUE,
+     &Type
+  } WITH SYNTAX {
+     ID &id TYPE &Type
+  }
+
+  obj CL ::= { ID 1 TYPE OCTET STRING }
+
+  pt-object{CL:ob} CL ::= {ID ob.&id TYPE OCTET STRING}
+
+END
diff --git a/lib/asn1/test/asn1_SUITE_data/Importing.asn1 b/lib/asn1/test/asn1_SUITE_data/Importing.asn1
new file mode 100644
index 0000000000..2f2699c576
--- /dev/null
+++ b/lib/asn1/test/asn1_SUITE_data/Importing.asn1
@@ -0,0 +1,20 @@
+Importing DEFINITIONS AUTOMATIC TAGS ::=
+BEGIN
+
+ Seq ::= Exporting.PtSeq{ INTEGER(0..7) }
+ OtherSeq ::= Exporting.Seq
+
+ seq Exporting.Seq ::= { id 42, f TRUE }
+
+ o1 Exporting.CL ::= { ID 2 TYPE INTEGER (0..63) }
+
+ ObjSet Exporting.CL ::= { o1 | Exporting.obj }
+
+ ObjSeq ::= SEQUENCE {
+   id Exporting.CL.&id ({ObjSet}),
+   type Exporting.CL.&Type ({ObjSet}{@id})
+ }
+
+ o1-cloned Exporting.CL ::= Exporting.pt-object{o1}
+
+END
diff --git a/lib/asn1/test/asn1_SUITE_data/InfObj.asn b/lib/asn1/test/asn1_SUITE_data/InfObj.asn
index aef20451cb..3b88770d78 100644
--- a/lib/asn1/test/asn1_SUITE_data/InfObj.asn
+++ b/lib/asn1/test/asn1_SUITE_data/InfObj.asn
@@ -463,4 +463,23 @@ Contents TYPE-IDENTIFIER ::= {
 ContentType ::= TYPE-IDENTIFIER.&id({Contents})
 id-content-type ContentType ::= { 2 7 8 9 }
 
+--
+-- Tricky parsing of simplified syntax.
+--
+
+TrickyType-1 ::= BIT STRING
+TrickyType-2 ::= OCTET STRING
+
+TRICKY ::= CLASS {
+  &Type1,
+  &Type2
+} WITH SYNTAX {
+   TYPE &Type1 &Type2
+}
+
+tricky-object TRICKY ::= {TYPE TrickyType-1 TrickyType-2}
+
+tricky-bit-string tricky-object.&Type1 ::= '1011'B
+tricky-octet-string tricky-object.&Type1 ::= 'CAFE'H
+
 END
diff --git a/lib/asn1/test/asn1_SUITE_data/MissingEnd.asn1 b/lib/asn1/test/asn1_SUITE_data/MissingEnd.asn1
deleted file mode 100644
index 66912ef693..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/MissingEnd.asn1
+++ /dev/null
@@ -1,5 +0,0 @@
-MissingEnd  DEFINITIONS ::=
-BEGIN
-
-T ::= Typ	
-
diff --git a/lib/asn1/test/asn1_SUITE_data/Seq.py b/lib/asn1/test/asn1_SUITE_data/Seq.py
index f345373ab5..b68f9045a6 100644
--- a/lib/asn1/test/asn1_SUITE_data/Seq.py
+++ b/lib/asn1/test/asn1_SUITE_data/Seq.py
@@ -142,7 +142,10 @@ SeqImp3 ::= SET
   set  Set1
 }
 
-
+SeqCompOf ::= SEQUENCE {
+  ...,
+  COMPONENTS OF SeqS3
+}
 
 END
 
diff --git a/lib/asn1/test/asn1_SUITE_data/SequenceBadComma.asn b/lib/asn1/test/asn1_SUITE_data/SequenceBadComma.asn
deleted file mode 100644
index 436815aa9b..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/SequenceBadComma.asn
+++ /dev/null
@@ -1,10 +0,0 @@
-SequenceBadComma DEFINITIONS IMPLICIT TAGS ::=
-BEGIN
-EXPORTS Person;
-
-Person ::= [PRIVATE 19] SEQUENCE {,
-    name PrintableString,
-    location INTEGER {home(0),field(1),roving(2)},
-    age INTEGER OPTIONAL
-    }
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentName.asn1 b/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentName.asn1
deleted file mode 100644
index 8b2b8816db..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentName.asn1
+++ /dev/null
@@ -1,10 +0,0 @@
-SequenceBadComponentName  DEFINITIONS ::=
-BEGIN
-
-T ::= Typ
-
-Typ ::= SEQUENCE {
-    a INTEGER,
-    C Typ}
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentType.asn1 b/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentType.asn1
deleted file mode 100644
index 0c33f48906..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/SequenceBadComponentType.asn1
+++ /dev/null
@@ -1,10 +0,0 @@
-SequenceBadComponentType  DEFINITIONS ::=
-BEGIN
-
-T ::= Typ
-
-Typ ::= SEQUENCE {
-    a b,
-    c T}
-
-END
diff --git a/lib/asn1/test/asn1_SUITE_data/Syntax.py b/lib/asn1/test/asn1_SUITE_data/Syntax.py
deleted file mode 100644
index 867d1148e1..0000000000
--- a/lib/asn1/test/asn1_SUITE_data/Syntax.py
+++ /dev/null
@@ -1,10 +0,0 @@
-Syntax DEFINITIONS IMPLICIT TAGS ::=
-BEGIN
-EXPORTS Person;
-
-Person ::= [PRIVATE 19] SEQUENCE {,
-	name PrintableString,
-	location INTEGER {home(0),field(1),roving(2)},
-	age INTEGER OPTIONAL
-	}
-END
diff --git a/lib/asn1/test/syntax_SUITE.erl b/lib/asn1/test/syntax_SUITE.erl
new file mode 100644
index 0000000000..f8d10157c0
--- /dev/null
+++ b/lib/asn1/test/syntax_SUITE.erl
@@ -0,0 +1,322 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2014. All Rights Reserved.
+%%
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(syntax_SUITE).
+-export([suite/0,all/0,groups/0,
+	 assignment/1,
+	 class/1,
+	 constraints/1,
+	 exports/1,
+	 header/1,
+	 imports/1,
+	 objects/1,
+	 sequence/1,
+	 syntax/1,
+	 types/1,
+	 values/1]).
+
+-include_lib("test_server/include/test_server.hrl").
+
+suite() -> [{ct_hooks, [ts_install_cth]}].
+
+all() ->
+    [{group,p}].
+
+groups() ->
+    [{p,parallel(),
+      [assignment,
+       class,
+       constraints,
+       exports,
+       header,
+       imports,
+       objects,
+       sequence,
+       syntax,
+       types,
+       values]}].
+
+parallel() ->
+    case erlang:system_info(schedulers) > 1 of
+        true  -> [parallel];
+        false -> []
+    end.
+
+assignment(Config) ->
+    Head = "Assignment DEFINITIONS AUTOMATIC TAGS ::=\nBEGIN\n",
+    End = "\nEND\n",
+    L0 = [{"42",3,{syntax_error,42}},
+	  {"i",4,{syntax_error,'END'}},
+	  {"i ::=",3,{syntax_error,'::='}},
+	  {"i type",4,{syntax_error,'END'}},
+	  {"i type ::=",3,{syntax_error,'::='}},
+	  {"i TYPE",4,{syntax_error,'END'}},
+	  {"i TYPE ::= ",4,{syntax_error,'END'}},
+	  {"i INTEGER ::= 42 garbage",4,{syntax_error,'END'}},
+	  {"i{T} Type",4,{syntax_error,'END'}},
+	  {"TYPE",4,{syntax_error,'END'}},
+	  {"TYPE ::=",4,{syntax_error,'END'}},
+	  {"TYPE{ ::=",3,{syntax_error,'::='}},
+	  {"TYPE{P, ::=",3,{syntax_error,'::='}},
+	  {"TYPE{P,} ::=",3,{syntax_error,'}'}},
+	  {"TYPE{Gov:} ::=",3,{syntax_error,':'}},
+	  {"TYPE{A} CL ",4,{syntax_error,'END'}},
+	  {"ObjSet CL",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Assignment", Config),
+    ok.
+
+class(Config) ->
+    Head = "Class DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	" CL ::= CLASS {",
+    End = "\nEND\n",
+    L0 = [{"id",3,{syntax_error,'id'}},
+	  {"&id INTEGER",4,{syntax_error,'END'}},
+	  {"&id INTEGER,",4,{syntax_error,'END'}},
+	  {"&id,",3,{syntax_error,','}},
+	  {"&id OPTIONAL",3,{syntax_error,'OPTIONAL'}},
+	  {"&id INTEGER OPTIONAL",4,{syntax_error,'END'}},
+	  {"&var &Field",4,{syntax_error,'END'}},
+	  {"&Type,",4,{syntax_error,'END'}},
+	  {"&Type OPTIONAL",4,{syntax_error,'END'}},
+	  {"&ValueSet INTEGER OPTIONAL",4,{syntax_error,'END'}},
+	  {"&ValueSet INTEGER DEFAULT",4,{syntax_error,'END'}},
+	  {"&ValueSet INTEGER DEFAULT {",4,{syntax_error,'END'}},
+	  {"&ValueSet INTEGER DEFAULT {a",4,{syntax_error,'END'}},
+	  {"&Var &Field",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Class", Config),
+    ok.
+
+constraints(Config) ->
+    Head = "Constraints DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	" Type ::= ",
+    End = "\nEND\n",
+    L0 = [{"INTEGER (",4,{syntax_error,'END'}},
+	  {"INTEGER (10x",3,{syntax_error,x}},
+	  {"INTEGER (10|(10y",3,{syntax_error,y}},
+	  {"INTEGER (CONSTRAINED BY {}",4,{syntax_error,'END'}},
+	  {"INTEGER (CONSTRAINED BY {INTEGER garbage",3,
+	   {syntax_error,garbage}},
+	  {"INTEGER ({ObjSet",4,{syntax_error,'END'}},
+	  {"INTEGER ({ObjSet}{",3,{syntax_error,'{'}},
+	  {"INTEGER ({ObjSet}{@",3,{syntax_error,'{'}},
+	  {"INTEGER ({ObjSet}{@x",3,{syntax_error,'{'}},
+	  {"INTEGER ({ObjSet}{@x}",4,{syntax_error,'END'}},
+	  {"INTEGER (10 !BOOLEAN",4,{syntax_error,'END'}},
+	  {"INTEGER (10 !BOOLEAN:",4,{syntax_error,'END'}},
+	  {"INTEGER (10 !BOOLEAN:FALSE",4,{syntax_error,'END'}},
+	  {"SEQUENCE {} (WITH COMPONENTS { Type })",
+	   3,{syntax_error,'Type'}},
+	  {"SEQUENCE {} (WITH COMPONENTS { x (10)",
+	   4,{syntax_error,'END'}},
+	  {"SEQUENCE {} (WITH COMPONENTS { ..., x (10)",
+	   4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Constraints", Config),
+    ok.
+
+exports(Config) ->
+    Head = "Exports DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	" EXPORTS ",
+    End = "\nEND\n",
+    L0 = [{"Type",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Exports", Config),
+    ok.
+
+header(Config) ->
+    L = [{"lowercase",1,{syntax_error,lowercase}},
+	 {"H ",2,{syntax_error,'END-OF-FILE'}},
+	 {"H-",1,{syntax_error,'-'}},
+	 {"42",1,{syntax_error,42}},
+	 {"H definitions",1,{syntax_error,definitions}},
+	 {"H DEFINITIONS STUPID TAGS",1,{syntax_error,'STUPID'}},
+	 {"H DEFINITIONS WHATEVER",1,{syntax_error,'WHATEVER'}},
+	 {"H DEFINITIONS ::= BEGIN",2,{syntax_error,'END-OF-FILE'}},
+	 {"BOOLEAN",1,{syntax_error,'BOOLEAN'}}
+	],
+    run(L, "H", Config),
+    ok.
+
+imports(Config) ->
+    Head = "Imports DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	" IMPORTS ",
+    End = "\nEND\n",
+    L0 = [{"Type FROM X",4,{syntax_error,'END'}},
+	  {"Symbols TO Y",3,{syntax_error,'TO'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Imports", Config),
+    ok.
+
+objects(Config) ->
+    Head = "Objects DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	"  object CLASS-NAME ::= ",
+    End = "\nEND\n",
+    L0 = [{"{",4,{syntax_error,'END'}},
+	  {"{&min 1, max 10}",3,{syntax_error,max}},
+	  {"{&min 1, Max 10}",3,{syntax_error,'Max'}},
+	  {"{min 1, &max 10}",3,{syntax_error,'&max'}},
+	  {"{min 1, &Max 10}",3,{syntax_error,'&Max'}},
+	  {"{RESERVERD WORD BIT}",3,{syntax_error,'BIT'}},
+	  {"{&min 1",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Objects", Config),
+    ok.
+
+sequence(Config) ->
+    Head = "Sequence DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	"  Type ::= SEQUENCE {",
+    End = "\nEND\n",
+    L0 = [{"",4,{syntax_error,'END'}},
+	  {" UpperCase",3,{syntax_error,'UpperCase'}},
+	  {" a b",4,{syntax_error,'END'}},
+	  {" i INTEGER",4,{syntax_error,'END'}},
+	  {" ...",4,{syntax_error,'END'}},
+	  {" ..., [[",4,{syntax_error,'END'}},
+	  {" ..., [[ a INTEGER ]",3,{syntax_error,']'}},
+	  {" ..., [[ a INTEGER,",3,{syntax_error,','}},
+	  {" ..., [[ a INTEGER, ... ]]",3,{syntax_error,','}},
+	  {" ... !42 xxx",3,{syntax_error,'xxx'}},
+	  {" ... !42, a INTEGER,",3,{syntax_error,','}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Sequence", Config),
+    ok.
+
+syntax(Config) ->
+    Head = "Syntax DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	" CL ::= CLASS { &id INTEGER UNIQUE } WITH SYNTAX ",
+    End = "\nEND\n",
+    L0 = [{"{}",3,{syntax_error,'}'}},
+	  {"WORD",3,{syntax_error,'WORD'}},
+	  {"{ Word }",3,{syntax_error,'Word'}},
+	  {"{ [ Word ] }",3,{syntax_error,'Word'}},
+	  {"{ [ WORD }",3,{syntax_error,'}'}},
+	  {"{ WORD;",3,{syntax_error,';'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Syntax", Config),
+    ok.
+
+types(Config) ->
+    Head = "Types DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	"  Type ::= ",
+    End = "\nEND\n",
+    L0 = [{"BIT STRING garbage",4,{syntax_error,'END'}},
+	  {"BIT STRING {",4,{syntax_error,'END'}},
+	  {"BIT STRING { a(42",3,{syntax_error,42}},
+	  {"BIT STRING { a(0)",4,{syntax_error,'END'}},
+	  {"CHOICE {",4,{syntax_error,'END'}},
+	  {"CHOICE { ..., a}",3,{syntax_error,'...'}},
+	  {"CHOICE { UpperCase",3,{syntax_error,'UpperCase'}},
+	  {"CHOICE { i INTEGER",4,{syntax_error,'END'}},
+	  {"CHOICE { ..., i INTEGER }",3,{syntax_error,'...'}},
+	  {"CHOICE { b BOOLEAN, ..., i INTEGER",
+	   4,{syntax_error,'END'}},
+	  {"CHOICE { b BOOLEAN, ..., [[ e BOOLEAN, ...]]}",
+	   3,{syntax_error,','}},
+	  {"CHOICE { b BOOLEAN, ..., i INTEGER, ..., x BIT STRING}",
+	   3,{syntax_error,','}},
+	  {"ENUMERATED {",4,{syntax_error,'END'}},
+	  {"ENUMERATED { 42 }",3,{syntax_error,42}},
+	  {"ENUMERATED { a, b",4,{syntax_error,'END'}},
+	  {"ENUMERATED { a, }",3,{syntax_error,','}},
+	  {"ENUMERATED { a, ...,\nb, ..., c }",4,{syntax_error,','}},
+	  {"INTEGER {",4,{syntax_error,'END'}},
+	  {"INTEGER { a(42)",4,{syntax_error,'END'}},
+	  {"SEQUENCE",3,{syntax_error,'SEQUENCE'}},
+	  %% More tests for SEQUENCE in sequence/1.
+	  {"SEQUENCE SIZE (1..10)",4,{syntax_error,'END'}},
+	  {"SEQUENCE (SIZE (1..10))",4,{syntax_error,'END'}},
+	  {"SET { i INTEGER",4,{syntax_error,'END'}},
+	  {"SET { ...",4,{syntax_error,'END'}},
+	  {"SET SIZE (1..10)",4,{syntax_error,'END'}},
+	  {"SET (SIZE (1..10))",4,{syntax_error,'END'}},
+	  {"SET { ... !42 xxx",3,{syntax_error,'xxx'}},
+	  {"SET { ... !42, a INTEGER,",3,{syntax_error,','}},
+	  {"[",4,{syntax_error,'END'}},
+	  {"[42",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Types", Config),
+    ok.
+
+values(Config) ->
+    Head = "Values DEFINITIONS AUTOMATIC TAGS ::=\n"
+	"BEGIN\n"
+	"  value Type ::= ",
+    End = "\nEND\n",
+    L0 = [{"",4,{syntax_error,'END'}}
+	 ],
+    L = [{Head++S++End,Line,E} || {S,Line,E} <- L0],
+    run(L, "Values", Config),
+    ok.
+
+run(List, File0, Config) ->
+    Base = File0 ++ ".asn1",
+    File = filename:join(?config(priv_dir, Config), Base),
+    case run_1(List, Base, File, 0) of
+	0 -> ok;
+	Errors -> ?t:fail(Errors)
+    end.
+
+run_1([{Source,Line,Error}=Exp|T], Base, File, N) ->
+    M = asn1ct_parser2,
+    ok = file:write_file(File, Source),
+    io:format("~s", [Source]),
+    case asn1ct:compile(File) of
+	{error,[{structured_error,{Base,L},M,E}]} ->
+	    case {L,E} of
+		{Line,Error} ->
+		    run_1(T, Base, File, N);
+		{Line,OtherError} ->
+		    io:format("*** Wrong error: ~p, expected ~p ***\n",
+			      [OtherError,Error]),
+		    run_1(T, Base, File, N+1);
+		{OtherLine,Error} ->
+		    io:format("*** Wrong line: ~p, expected ~p ***\n",
+			      [OtherLine,Line]),
+		    run_1(T, Base, File, N+1);
+		{_,_} ->
+		    io:format("*** Wrong line: ~p, expected ~p ***",
+			      [L,Line]),
+		    io:format("*** Wrong error: ~p, expected ~p ***\n",
+			      [E,Error]),
+		    run_1(T, Base, File, N+1)
+	    end;
+	Other ->
+	    io:format("~p\nGOT: ~p", [Exp,Other])
+    end;
+run_1([], _, _, N) ->
+    N.
diff --git a/lib/asn1/test/testChoExtension.erl b/lib/asn1/test/testChoExtension.erl
index 09e19ceebb..f36d6c1cbf 100644
--- a/lib/asn1/test/testChoExtension.erl
+++ b/lib/asn1/test/testChoExtension.erl
@@ -39,11 +39,6 @@ extension(_Rules) ->
     roundtrip('ChoExt3', {int,33}),
     roundtrip('ChoExt4', {str,<<"abc">>}),
 
-    roundtrip('ChoEmptyRoot', {bool,false}),
-    roundtrip('ChoEmptyRoot', {bool,true}),
-    roundtrip('ChoEmptyRoot', {int,0}),
-    roundtrip('ChoEmptyRoot', {int,7}),
-
     ok.
 
 
diff --git a/lib/asn1/test/testImporting.erl b/lib/asn1/test/testImporting.erl
new file mode 100644
index 0000000000..de8beae38b
--- /dev/null
+++ b/lib/asn1/test/testImporting.erl
@@ -0,0 +1,34 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2014. All Rights Reserved.
+%%
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%%
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%
+
+-module(testImporting).
+-export([main/0]).
+
+main() ->
+    M = 'Importing',
+    roundtrip('Seq', {'Seq',5}),
+    roundtrip('OtherSeq', {'Seq',42,true}),
+    {'Seq',42,true} = M:seq(),
+    roundtrip('ObjSeq', {'ObjSeq',1,<<"XYZ">>}),
+    roundtrip('ObjSeq', {'ObjSeq',2,19}),
+    ok.
+
+roundtrip(Type, Value) ->
+    asn1_test_lib:roundtrip('Importing', Type, Value).
diff --git a/lib/asn1/test/testInfObj.erl b/lib/asn1/test/testInfObj.erl
index bcd4755003..3044d5cd2a 100644
--- a/lib/asn1/test/testInfObj.erl
+++ b/lib/asn1/test/testInfObj.erl
@@ -166,6 +166,9 @@ main(_Erule) ->
 	      {'ContentInfo',{2,7,8,9},"string"}),
     {2,7,8,9} = 'InfObj':'id-content-type'(),
 
+    <<2#1011:4>> = 'InfObj':'tricky-bit-string'(),
+    <<16#CAFE:16>> = 'InfObj':'tricky-octet-string'(),
+
     ok.
 
 test_objset(Type, Keys) ->