[stdlib, kernel] Introduce Unicode support for Erlang source files

Expect modifications, additions and corrections.

There is a kludge in file_io_server and
erl_scan:continuation_location() that's not so pleasing.

1 files changed, 401 insertions, 358 deletions

diff --git a/lib/stdlib/src/erl_pp.erl b/lib/stdlib/src/erl_pp.erl
index 6b5aa951cf..0383ce6839 100644
--- a/lib/stdlib/src/erl_pp.erl
+++ b/lib/stdlib/src/erl_pp.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1996-2011. All Rights Reserved.
+%% Copyright Ericsson AB 1996-2012. 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
@@ -26,7 +26,7 @@
          guard/1,guard/2,exprs/1,exprs/2,exprs/3,expr/1,expr/2,expr/3,expr/4]).
 
 -import(lists, [append/1,foldr/3,mapfoldl/3,reverse/1,reverse/2]).
--import(io_lib, [write/1,format/2,write_char/1,write_string/1]).
+-import(io_lib, [write/1,format/2]).
 -import(erl_parse, [inop_prec/1,preop_prec/1,func_prec/0,max_prec/0]).
 
 -define(MAXLINE, 72).
@@ -36,7 +36,15 @@
                               CurrentIndentation :: integer(),
                               CurrentPrecedence :: non_neg_integer(),
                               HookFunction :: hook_function()) ->
-                                    io_lib:chars())).
+                                   io_lib:chars())).
+
+-type(option() :: {hook, hook_function()}
+                | {encoding, latin1 | unicode | utf8}).
+-type(options() :: hook_function() | [option()]).
+
+-record(pp, {string_fun, char_fun}).
+
+-record(options, {hook, encoding, opts}).
 
 %%%
 %%% Exported functions
@@ -48,12 +56,12 @@
 form(Thing) ->
     form(Thing, none).
 
--spec(form(Form, HookFunction) -> io_lib:chars() when
+-spec(form(Form, Options) -> io_lib:chars() when
       Form :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-form(Thing, Hook) ->
-    frmt(lform(Thing, Hook)).
+form(Thing, Options) ->
+    frmt(lform(Thing, options(Options)), state(Options)).
 
 -spec(attribute(Attribute) -> io_lib:chars() when
       Attribute :: erl_parse:abstract_form()).
@@ -61,12 +69,12 @@ form(Thing, Hook) ->
 attribute(Thing) ->
     attribute(Thing, none).
 
--spec(attribute(Attribute, HookFunction) -> io_lib:chars() when
+-spec(attribute(Attribute, Options) -> io_lib:chars() when
       Attribute :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-attribute(Thing, Hook) ->
-    frmt(lattribute(Thing, Hook)).
+attribute(Thing, Options) ->
+    frmt(lattribute(Thing, options(Options)), state(Options)).
 
 -spec(function(Function) -> io_lib:chars() when
       Function :: erl_parse:abstract_form()).
@@ -74,18 +82,18 @@ attribute(Thing, Hook) ->
 function(F) ->
     function(F, none).
 
--spec(function(Function, HookFunction) -> io_lib:chars() when
+-spec(function(Function, Options) -> io_lib:chars() when
       Function :: erl_parse:abstract_form(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-function(F, Hook) ->
-    frmt(lfunction(F, Hook)).
+function(F, Options) ->
+    frmt(lfunction(F, options(Options)), state(Options)).
 
 rule(R) ->
     rule(R, none).
 
-rule(R, Hook) ->
-    frmt(lrule(R, Hook)).
+rule(R, Options) ->
+    frmt(lrule(R, options(Options)), state(Options)).
 
 -spec(guard(Guard) -> io_lib:chars() when
       Guard :: [erl_parse:abstract_expr()]).
@@ -93,12 +101,12 @@ rule(R, Hook) ->
 guard(Gs) ->
     guard(Gs, none).
 
--spec(guard(Guard, HookFunction) -> io_lib:chars() when
+-spec(guard(Guard, Options) -> io_lib:chars() when
       Guard :: [erl_parse:abstract_expr()],
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-guard(Gs, Hook) ->
-    frmt(lguard(Gs, Hook)).
+guard(Gs, Options) ->
+    frmt(lguard(Gs, options(Options)), state(Options)).
 
 -spec(exprs(Expressions) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()]).
@@ -106,99 +114,129 @@ guard(Gs, Hook) ->
 exprs(Es) ->
     exprs(Es, 0, none).
 
--spec(exprs(Expressions, HookFunction) -> io_lib:chars() when
+-spec(exprs(Expressions, Options) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()],
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-exprs(Es, Hook) ->
-    exprs(Es, 0, Hook).
+exprs(Es, Options) ->
+    exprs(Es, 0, Options).
 
--spec(exprs(Expressions, Indent, HookFunction) -> io_lib:chars() when
+-spec(exprs(Expressions, Indent, Options) -> io_lib:chars() when
       Expressions :: [erl_parse:abstract_expr()],
       Indent :: integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-exprs(Es, I, Hook) ->
-    frmt({seq,[],[],[$,],lexprs(Es, Hook)}, I).
+exprs(Es, I, Options) ->
+    frmt({seq,[],[],[$,],lexprs(Es, options(Options))}, I, state(Options)).
 
 -spec(expr(Expression) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr()).
 
 expr(E) ->
-    frmt(lexpr(E, 0, none)).
+    frmt(lexpr(E, 0, options(none)), state(none)).
 
--spec(expr(Expression, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, Hook) ->
-    frmt(lexpr(E, 0, Hook)).
+expr(E, Options) ->
+    frmt(lexpr(E, 0, options(Options)), state(Options)).
 
--spec(expr(Expression, Indent, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Indent, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
       Indent :: integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, I, Hook) ->
-    frmt(lexpr(E, 0, Hook), I).
+expr(E, I, Options) ->
+    frmt(lexpr(E, 0, options(Options)), I, state(Options)).
 
--spec(expr(Expression, Indent, Precedence, HookFunction) -> io_lib:chars() when
+-spec(expr(Expression, Indent, Precedence, Options) -> io_lib:chars() when
       Expression :: erl_parse:abstract_expr(),
       Indent :: integer(),
       Precedence :: non_neg_integer(),
-      HookFunction :: hook_function()).
+      Options :: options()).
 
-expr(E, I, P, Hook) ->
-    frmt(lexpr(E, P, Hook), I).
+expr(E, I, P, Options) ->
+    frmt(lexpr(E, P, options(Options)), I, state(Options)).
 
 %%%
 %%% Local functions
 %%%
 
-lform({attribute,Line,Name,Arg}, Hook) ->
-    lattribute({attribute,Line,Name,Arg}, Hook);
-lform({function,Line,Name,Arity,Clauses}, Hook) ->
-    lfunction({function,Line,Name,Arity,Clauses}, Hook);
-lform({rule,Line,Name,Arity,Clauses}, Hook) ->
-    lrule({rule,Line,Name,Arity,Clauses}, Hook);
+options(Options) when is_list(Options) ->
+    Hook = proplists:get_value(hook, Options, none),
+    Encoding = encoding(Options),
+    #options{hook = Hook, encoding = Encoding, opts = Options};
+options(Hook) ->
+    #options{hook = Hook, encoding = encoding([]), opts = Hook}.
+
+state(Options) when is_list(Options) ->
+    case encoding(Options) of
+        latin1 -> state();
+        unicode -> unicode_state()
+    end;
+state(_Hook) ->
+    state().
+
+state() ->
+    #pp{string_fun = fun io_lib:write_unicode_string_as_latin1/1,
+        char_fun   = fun io_lib:write_unicode_char_as_latin1/1}.
+
+unicode_state() ->
+    #pp{string_fun = fun io_lib:write_unicode_string/1,
+        char_fun   = fun io_lib:write_unicode_char/1}.
+
+encoding(Options) ->
+    case proplists:get_value(encoding, Options, epp:default_encoding()) of
+        latin1 -> latin1;
+        utf8 -> unicode;
+        unicode -> unicode
+    end.
+
+lform({attribute,Line,Name,Arg}, Opts) ->
+    lattribute({attribute,Line,Name,Arg}, Opts);
+lform({function,Line,Name,Arity,Clauses}, Opts) ->
+    lfunction({function,Line,Name,Arity,Clauses}, Opts);
+lform({rule,Line,Name,Arity,Clauses}, Opts) ->
+    lrule({rule,Line,Name,Arity,Clauses}, Opts);
 %% These are specials to make it easier for the compiler.
-lform({error,E}, _Hook) ->
+lform({error,E}, _Opts) ->
     leaf(format("~p\n", [{error,E}]));
-lform({warning,W}, _Hook) ->
+lform({warning,W}, _Opts) ->
     leaf(format("~p\n", [{warning,W}]));
-lform({eof,_Line}, _Hook) ->
+lform({eof,_Line}, _Opts) ->
     $\n.
 
-lattribute({attribute,_Line,type,Type}, Hook) ->
-    [typeattr(type, Type, Hook),leaf(".\n")];
-lattribute({attribute,_Line,opaque,Type}, Hook) ->
-    [typeattr(opaque, Type, Hook),leaf(".\n")];
-lattribute({attribute,_Line,spec,Arg}, _Hook) ->
+lattribute({attribute,_Line,type,Type}, Opts) ->
+    [typeattr(type, Type, Opts),leaf(".\n")];
+lattribute({attribute,_Line,opaque,Type}, Opts) ->
+    [typeattr(opaque, Type, Opts),leaf(".\n")];
+lattribute({attribute,_Line,spec,Arg}, _Opts) ->
     [specattr(Arg),leaf(".\n")];
-lattribute({attribute,_Line,Name,Arg}, Hook) ->
-    [lattribute(Name, Arg, Hook),leaf(".\n")].
+lattribute({attribute,_Line,Name,Arg}, Opts) ->
+    [lattribute(Name, Arg, Opts),leaf(".\n")].
 
-lattribute(module, {M,Vs}, _Hook) ->
+lattribute(module, {M,Vs}, _Opts) ->
     attr("module",[{var,0,pname(M)},
                    foldr(fun(V, C) -> {cons,0,{var,0,V},C}
                          end, {nil,0}, Vs)]);
-lattribute(module, M, _Hook) ->
+lattribute(module, M, _Opts) ->
     attr("module", [{var,0,pname(M)}]);
-lattribute(export, Falist, _Hook) ->
+lattribute(export, Falist, _Opts) ->
     call({var,0,"-export"}, [falist(Falist)], 0, none);
-lattribute(import, Name, _Hook) when is_list(Name) ->
+lattribute(import, Name, _Opts) when is_list(Name) ->
     attr("import", [{var,0,pname(Name)}]);
-lattribute(import, {From,Falist}, _Hook) ->
+lattribute(import, {From,Falist}, _Opts) ->
     attr("import",[{var,0,pname(From)},falist(Falist)]);
-lattribute(file, {Name,Line}, _Hook) ->
+lattribute(file, {Name,Line}, _Opts) ->
     attr("file", [{var,0,format("~p", [Name])},{integer,0,Line}]);
-lattribute(record, {Name,Is}, Hook) ->
+lattribute(record, {Name,Is}, Opts) ->
     Nl = leaf(format("-record(~w,", [Name])),
-    [{first,Nl,record_fields(Is, Hook)},$)];
-lattribute(Name, Arg, _Hook) ->
-    attr(write(Name), [erl_parse:abstract(Arg)]).
+    [{first,Nl,record_fields(Is, Opts)},$)];
+lattribute(Name, Arg, #options{encoding = Encoding}) ->
+    attr(write(Name), [erl_parse:abstract(Arg, [{encoding,Encoding}])]).
 
-typeattr(Tag, {TypeName,Type,Args}, _Hook) ->
+typeattr(Tag, {TypeName,Type,Args}, _Opts) ->
     {first,leaf("-"++atom_to_list(Tag)++" "),
      typed(call({atom,0,TypeName}, Args, 0, none), Type)}.
 
@@ -293,7 +331,7 @@ guard_type(Before, Gs) ->
     Gl = {list,[{step,'when',expr_list(Gs, [$,], fun constraint/2, none)}]},
     {list,[{step,Before,Gl}]}.
 
-constraint({type,_Line,constraint,[Tag,As]}, _Hook) ->
+constraint({type,_Line,constraint,[Tag,As]}, _Opts) ->
     simple_type(Tag, As).
 
 fun_type(Before, {type,_,'fun',[FType,Ret]}) ->
@@ -333,231 +371,232 @@ falist([]) ->
 falist([{Name,Arity}|Falist]) ->
     {cons,0,{var,0,format("~w/~w", [Name,Arity])},falist(Falist)}.
 
-lfunction({function,_Line,Name,_Arity,Cs}, Hook) ->
-    Cll = nl_clauses(fun (C, H) -> func_clause(Name, C, H) end, $;, Hook, Cs),
+lfunction({function,_Line,Name,_Arity,Cs}, Opts) ->
+    Cll = nl_clauses(fun (C, H) -> func_clause(Name, C, H) end, $;, Opts, Cs),
     [Cll,leaf(".\n")].
 
-func_clause(Name, {clause,Line,Head,Guard,Body}, Hook) ->
-    Hl = call({atom,Line,Name}, Head, 0, Hook),
-    Gl = guard_when(Hl, Guard, Hook),
-    Bl = body(Body, Hook),
+func_clause(Name, {clause,Line,Head,Guard,Body}, Opts) ->
+    Hl = call({atom,Line,Name}, Head, 0, Opts),
+    Gl = guard_when(Hl, Guard, Opts),
+    Bl = body(Body, Opts),
     {step,Gl,Bl}.
 
-lrule({rule,_Line,Name,_Arity,Cs}, Hook) ->
-    Cll = nl_clauses(fun (C, H) -> rule_clause(Name, C, H) end, $;, Hook, Cs),
+lrule({rule,_Line,Name,_Arity,Cs}, Opts) ->
+    Cll = nl_clauses(fun (C, H) -> rule_clause(Name, C, H) end, $;, Opts, Cs),
     [Cll,leaf(".\n")].
 
-rule_clause(Name, {clause,Line,Head,Guard,Body}, Hook) ->
-    Hl = call({atom,Line,Name}, Head, 0, Hook),
-    Gl = guard_when(Hl, Guard, Hook, leaf(" :-")),
-    Bl = rule_body(Body, Hook),
+rule_clause(Name, {clause,Line,Head,Guard,Body}, Opts) ->
+    Hl = call({atom,Line,Name}, Head, 0, Opts),
+    Gl = guard_when(Hl, Guard, Opts, leaf(" :-")),
+    Bl = rule_body(Body, Opts),
     {step,Gl,Bl}.
 
-rule_body(Es, Hook) ->
-    lc_quals(Es, Hook).
+rule_body(Es, Opts) ->
+    lc_quals(Es, Opts).
 
-guard_when(Before, Guard, Hook) ->
-    guard_when(Before, Guard, Hook, ' ->').
+guard_when(Before, Guard, Opts) ->
+    guard_when(Before, Guard, Opts, ' ->').
 
-guard_when(Before, Guard, Hook, After) ->
-    Gl = lguard(Guard, Hook),
+guard_when(Before, Guard, Opts, After) ->
+    Gl = lguard(Guard, Opts),
     [{list,[{step,Before,Gl}]},After].
 
-lguard([E|Es], Hook) when is_list(E) ->
-    {list,[{step,'when',expr_list([E|Es], [$;], fun guard0/2, Hook)}]};
-lguard([E|Es], Hook) -> % before R6
-    lguard([[E|Es]], Hook);
+lguard([E|Es], Opts) when is_list(E) ->
+    {list,[{step,'when',expr_list([E|Es], [$;], fun guard0/2, Opts)}]};
+lguard([E|Es], Opts) -> % before R6
+    lguard([[E|Es]], Opts);
 lguard([], _) ->
     [].
 
-guard0(Es, Hook) ->
-    expr_list(Es, [$,], fun lexpr/2, Hook).
+guard0(Es, Opts) ->
+    expr_list(Es, [$,], fun lexpr/2, Opts).
 
-%% body(Before, Es, Hook) -> [Char].
+%% body(Before, Es, Opts) -> [Char].
 
-body([E], Hook) ->
-    lexpr(E, Hook);
-body(Es, Hook) ->
-    {prefer_nl,[$,],lexprs(Es, Hook)}.
+body([E], Opts) ->
+    lexpr(E, Opts);
+body(Es, Opts) ->
+    {prefer_nl,[$,],lexprs(Es, Opts)}.
 
-lexpr(E, Hook) ->
-    lexpr(E, 0, Hook).
+lexpr(E, Opts) ->
+    lexpr(E, 0, Opts).
 
 lexpr({var,_,V}, _, _) when is_integer(V) ->    %Special hack for Robert
     leaf(format("_~w", [V]));
 lexpr({var,_,V}, _, _) -> leaf(format("~s", [V]));
-lexpr({char,_,C}, _, _) -> leaf(write_char(C));
+lexpr({char,_,C}, _, _) -> {char,C};
 lexpr({integer,_,N}, _, _) -> leaf(write(N));
 lexpr({float,_,F}, _, _) -> leaf(write(F));
 lexpr({atom,_,A}, _, _) -> leaf(write(A));
 lexpr({string,_,S}, _, _) -> {string,S};
 lexpr({nil,_}, _, _) -> '[]';
-lexpr({cons,_,H,T}, _, Hook) ->
-    list(T, [H], Hook);
-lexpr({lc,_,E,Qs}, _Prec, Hook) ->
-    Lcl = {list,[{step,[lexpr(E, Hook),leaf(" ||")],lc_quals(Qs, Hook)}]},
+lexpr({cons,_,H,T}, _, Opts) ->
+    list(T, [H], Opts);
+lexpr({lc,_,E,Qs}, _Prec, Opts) ->
+    Lcl = {list,[{step,[lexpr(E, Opts),leaf(" ||")],lc_quals(Qs, Opts)}]},
     {list,[{seq,$[,[],[[]],[{force_nl,leaf(" "),[Lcl]}]},$]]};
     %% {list,[{step,$[,Lcl},$]]};
-lexpr({bc,_,E,Qs}, _Prec, Hook) ->
-    Lcl = {list,[{step,[lexpr(E, Hook),leaf(" ||")],lc_quals(Qs, Hook)}]},
+lexpr({bc,_,E,Qs}, _Prec, Opts) ->
+    Lcl = {list,[{step,[lexpr(E, Opts),leaf(" ||")],lc_quals(Qs, Opts)}]},
     {list,[{seq,'<<',[],[[]],[{force_nl,leaf(" "),[Lcl]}]},'>>']};
     %% {list,[{step,'<<',Lcl},'>>']};
-lexpr({tuple,_,Elts}, _, Hook) ->
-    tuple(Elts, Hook);
-%%lexpr({struct,_,Tag,Elts}, _, Hook) ->
-%%  {first,format("~w", [Tag]),tuple(Elts, Hook)};
-lexpr({record_index, _, Name, F}, Prec, Hook) ->
+lexpr({tuple,_,Elts}, _, Opts) ->
+    tuple(Elts, Opts);
+%%lexpr({struct,_,Tag,Elts}, _, Opts) ->
+%%  {first,format("~w", [Tag]),tuple(Elts, Opts)};
+lexpr({record_index, _, Name, F}, Prec, Opts) ->
     {P,R} = preop_prec('#'),
     Nl = record_name(Name),
-    El = [Nl,$.,lexpr(F, R, Hook)],
+    El = [Nl,$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record, _, Name, Fs}, Prec, Hook) ->
+lexpr({record, _, Name, Fs}, Prec, Opts) ->
     {P,_R} = preop_prec('#'),
     Nl = record_name(Name),
-    El = {first,Nl,record_fields(Fs, Hook)},
+    El = {first,Nl,record_fields(Fs, Opts)},
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, Rec, Name, F}, Prec, Hook) ->
+lexpr({record_field, _, Rec, Name, F}, Prec, Opts) ->
     {L,P,R} = inop_prec('#'),
-    Rl = lexpr(Rec, L, Hook),
+    Rl = lexpr(Rec, L, Opts),
     Nl = leaf(format("#~w.", [Name])),
-    El = [Rl,Nl,lexpr(F, R, Hook)],
+    El = [Rl,Nl,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record, _, Rec, Name, Fs}, Prec, Hook) ->
+lexpr({record, _, Rec, Name, Fs}, Prec, Opts) ->
     {L,P,_R} = inop_prec('#'),
-    Rl = lexpr(Rec, L, Hook),
+    Rl = lexpr(Rec, L, Opts),
     Nl = record_name(Name),
-    El = {first,[Rl,Nl],record_fields(Fs, Hook)},
+    El = {first,[Rl,Nl],record_fields(Fs, Opts)},
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, {atom,_,''}, F}, Prec, Hook) ->
+lexpr({record_field, _, {atom,_,''}, F}, Prec, Opts) ->
     {_L,P,R} = inop_prec('.'),
-    El = [$.,lexpr(F, R, Hook)],
+    El = [$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({record_field, _, Rec, F}, Prec, Hook) ->
+lexpr({record_field, _, Rec, F}, Prec, Opts) ->
     {L,P,R} = inop_prec('.'),
-    El = [lexpr(Rec, L, Hook),$.,lexpr(F, R, Hook)],
+    El = [lexpr(Rec, L, Opts),$.,lexpr(F, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({block,_,Es}, _, Hook) ->
-    {list,[{step,'begin',body(Es, Hook)},'end']};
-lexpr({'if',_,Cs}, _, Hook) ->
-    {list,[{step,'if',if_clauses(Cs, Hook)},'end']};
-lexpr({'case',_,Expr,Cs}, _, Hook) ->
-    {list,[{step,{list,[{step,'case',lexpr(Expr, Hook)},'of']},
-            cr_clauses(Cs, Hook)},
+lexpr({block,_,Es}, _, Opts) ->
+    {list,[{step,'begin',body(Es, Opts)},'end']};
+lexpr({'if',_,Cs}, _, Opts) ->
+    {list,[{step,'if',if_clauses(Cs, Opts)},'end']};
+lexpr({'case',_,Expr,Cs}, _, Opts) ->
+    {list,[{step,{list,[{step,'case',lexpr(Expr, Opts)},'of']},
+            cr_clauses(Cs, Opts)},
            'end']};
-lexpr({'cond',_,Cs}, _, Hook) ->
-    {list,[{step,leaf("cond"),cond_clauses(Cs, Hook)},'end']};
-lexpr({'receive',_,Cs}, _, Hook) ->
-    {list,[{step,'receive',cr_clauses(Cs, Hook)},'end']};
-lexpr({'receive',_,Cs,To,ToOpt}, _, Hook) ->
-    Al = {list,[{step,[lexpr(To, Hook),' ->'],body(ToOpt, Hook)}]},
-    {list,[{step,'receive',cr_clauses(Cs, Hook)},
+lexpr({'cond',_,Cs}, _, Opts) ->
+    {list,[{step,leaf("cond"),cond_clauses(Cs, Opts)},'end']};
+lexpr({'receive',_,Cs}, _, Opts) ->
+    {list,[{step,'receive',cr_clauses(Cs, Opts)},'end']};
+lexpr({'receive',_,Cs,To,ToOpt}, _, Opts) ->
+    Al = {list,[{step,[lexpr(To, Opts),' ->'],body(ToOpt, Opts)}]},
+    {list,[{step,'receive',cr_clauses(Cs, Opts)},
            {step,'after',Al},
            'end']};
-lexpr({'fun',_,{function,F,A}}, _Prec, _Hook) ->
+lexpr({'fun',_,{function,F,A}}, _Prec, _Opts) ->
     leaf(format("fun ~w/~w", [F,A]));
-lexpr({'fun',_,{function,F,A},Extra}, _Prec, _Hook) ->
+lexpr({'fun',_,{function,F,A},Extra}, _Prec, _Opts) ->
     {force_nl,fun_info(Extra),leaf(format("fun ~w/~w", [F,A]))};
-lexpr({'fun',_,{function,M,F,A}}, _Prec, _Hook)
+lexpr({'fun',_,{function,M,F,A}}, _Prec, _Opts)
   when is_atom(M), is_atom(F), is_integer(A) ->
     %% For backward compatibility with pre-R15 abstract format.
     leaf(format("fun ~w:~w/~w", [M,F,A]));
-lexpr({'fun',_,{function,M,F,A}}, _Prec, Hook) ->
+lexpr({'fun',_,{function,M,F,A}}, _Prec, Opts) ->
     %% New format in R15.
-    NameItem = lexpr(M, Hook),
-    CallItem = lexpr(F, Hook),
-    ArityItem = lexpr(A, Hook),
+    NameItem = lexpr(M, Opts),
+    CallItem = lexpr(F, Opts),
+    ArityItem = lexpr(A, Opts),
     ["fun ",NameItem,$:,CallItem,$/,ArityItem];
-lexpr({'fun',_,{clauses,Cs}}, _Prec, Hook) ->
-    {list,[{first,'fun',fun_clauses(Cs, Hook)},'end']};
-lexpr({'fun',_,{clauses,Cs},Extra}, _Prec, Hook) ->
+lexpr({'fun',_,{clauses,Cs}}, _Prec, Opts) ->
+    {list,[{first,'fun',fun_clauses(Cs, Opts)},'end']};
+lexpr({'fun',_,{clauses,Cs},Extra}, _Prec, Opts) ->
     {force_nl,fun_info(Extra),
-     {list,[{first,'fun',fun_clauses(Cs, Hook)},'end']}};
-lexpr({'query',_,Lc}, _Prec, Hook) ->
-    {list,[{step,leaf("query"),lexpr(Lc, 0, Hook)},'end']};
-lexpr({call,_,{remote,_,{atom,_,M},{atom,_,F}=N}=Name,Args}, Prec, Hook) ->
+     {list,[{first,'fun',fun_clauses(Cs, Opts)},'end']}};
+lexpr({'query',_,Lc}, _Prec, Opts) ->
+    {list,[{step,leaf("query"),lexpr(Lc, 0, Opts)},'end']};
+lexpr({call,_,{remote,_,{atom,_,M},{atom,_,F}=N}=Name,Args}, Prec, Opts) ->
     case erl_internal:bif(M, F, length(Args)) of
         true ->
-            call(N, Args, Prec, Hook);
+            call(N, Args, Prec, Opts);
         false ->
-            call(Name, Args, Prec, Hook)
+            call(Name, Args, Prec, Opts)
     end;
-lexpr({call,_,Name,Args}, Prec, Hook) ->
-    call(Name, Args, Prec, Hook);
-lexpr({'try',_,Es,Scs,Ccs,As}, _, Hook) ->
+lexpr({call,_,Name,Args}, Prec, Opts) ->
+    call(Name, Args, Prec, Opts);
+lexpr({'try',_,Es,Scs,Ccs,As}, _, Opts) ->
     {list,[if
                Scs =:= [] ->
-                   {step,'try',body(Es, Hook)};
+                   {step,'try',body(Es, Opts)};
                true ->
-                   {step,{list,[{step,'try',body(Es, Hook)},'of']},
-                    cr_clauses(Scs, Hook)}
+                   {step,{list,[{step,'try',body(Es, Opts)},'of']},
+                    cr_clauses(Scs, Opts)}
            end,
            if
                Ccs =:= [] ->
                    [];
                true ->
-                   {step,'catch',try_clauses(Ccs, Hook)}
+                   {step,'catch',try_clauses(Ccs, Opts)}
            end,
            if
                As =:= [] ->
                    [];
                true ->
-                   {step,'after',body(As, Hook)}
+                   {step,'after',body(As, Opts)}
            end,
            'end']};
-lexpr({'catch',_,Expr}, Prec, Hook) ->
+lexpr({'catch',_,Expr}, Prec, Opts) ->
     {P,R} = preop_prec('catch'),
-    El = {list,[{step,'catch',lexpr(Expr, R, Hook)}]},
+    El = {list,[{step,'catch',lexpr(Expr, R, Opts)}]},
     maybe_paren(P, Prec, El);
-lexpr({match,_,Lhs,Rhs}, Prec, Hook) ->
+lexpr({match,_,Lhs,Rhs}, Prec, Opts) ->
     {L,P,R} = inop_prec('='),
-    Pl = lexpr(Lhs, L, Hook),
-    Rl = lexpr(Rhs, R, Hook),
+    Pl = lexpr(Lhs, L, Opts),
+    Rl = lexpr(Rhs, R, Opts),
     El = {list,[{cstep,[Pl,' ='],Rl}]},
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Arg}, Prec, Hook) ->
+lexpr({op,_,Op,Arg}, Prec, Opts) ->
     {P,R} = preop_prec(Op),
     Ol = leaf(format("~s ", [Op])),
-    El = [Ol,lexpr(Arg, R, Hook)],
+    El = [Ol,lexpr(Arg, R, Opts)],
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Larg,Rarg}, Prec, Hook)  when Op =:= 'orelse';
+lexpr({op,_,Op,Larg,Rarg}, Prec, Opts)  when Op =:= 'orelse';
                                              Op =:= 'andalso' ->
     %% Breaks lines since R12B.
     {L,P,R} = inop_prec(Op),
-    Ll = lexpr(Larg, L, Hook),
+    Ll = lexpr(Larg, L, Opts),
     Ol = leaf(format("~s", [Op])),
-    Lr = lexpr(Rarg, R, Hook),
+    Lr = lexpr(Rarg, R, Opts),
     El = {prefer_nl,[[]],[Ll,Ol,Lr]},
     maybe_paren(P, Prec, El);
-lexpr({op,_,Op,Larg,Rarg}, Prec, Hook) ->
+lexpr({op,_,Op,Larg,Rarg}, Prec, Opts) ->
     {L,P,R} = inop_prec(Op),
-    Ll = lexpr(Larg, L, Hook),
+    Ll = lexpr(Larg, L, Opts),
     Ol = leaf(format("~s", [Op])),
-    Lr = lexpr(Rarg, R, Hook),
+    Lr = lexpr(Rarg, R, Opts),
     El = {list,[Ll,Ol,Lr]},
     maybe_paren(P, Prec, El);
 %% Special expressions which are not really legal everywhere.
-lexpr({remote,_,M,F}, Prec, Hook) ->
+lexpr({remote,_,M,F}, Prec, Opts) ->
     {L,P,R} = inop_prec(':'),
-    NameItem = lexpr(M, L, Hook),
-    CallItem = lexpr(F, R, Hook),
+    NameItem = lexpr(M, L, Opts),
+    CallItem = lexpr(F, R, Opts),
     maybe_paren(P, Prec, [NameItem,$:,CallItem]);
 %% BIT SYNTAX:
-lexpr({bin,_,Fs}, _, Hook) ->
-    bit_grp(Fs, Hook);
+lexpr({bin,_,Fs}, _, Opts) ->
+    bit_grp(Fs, Opts);
 %% Special case for straight values.
 lexpr({value,_,Val}, _,_) ->
     leaf(write(Val));
 %% Now do the hook.
-lexpr(Other, _Precedence, none) ->
+lexpr(Other, _Precedence, #options{hook = none}) ->
     leaf(format("INVALID-FORM:~w:",[Other]));
-lexpr(HookExpr, Precedence, {Mod,Func,Eas}) when Mod =/= 'fun' ->
+lexpr(HookExpr, Precedence, #options{hook = {Mod,Func,Eas}})
+                                        when Mod =/= 'fun' ->
     {ehook,HookExpr,Precedence,{Mod,Func,Eas}};
-lexpr(HookExpr, Precedence, Func) ->
-    {hook,HookExpr,Precedence,Func}.
+lexpr(HookExpr, Precedence, #options{hook = Func, opts = Options}) ->
+    {hook,HookExpr,Precedence,Func,Options}.
 
-call(Name, Args, Prec, Hook) ->
+call(Name, Args, Prec, Opts) ->
     {F,P} = func_prec(),
-    Item = {first,lexpr(Name, F, Hook),args(Args, Hook)},
+    Item = {first,lexpr(Name, F, Opts),args(Args, Opts)},
     maybe_paren(P, Prec, Item).
 
 fun_info(Extra) ->
@@ -565,32 +604,18 @@ fun_info(Extra) ->
 
 %% BITS:
 
-bit_grp(Fs, Hook) ->
-    append([['<<'],
-            [try
-                 true = Fs =/= [],
-                 S = bin_string(Fs),
-                 true = io_lib:printable_list(S),
-                 {string,S}
-             catch _:_ ->
-                 bit_elems(Fs, Hook)
-             end],
-            ['>>']]).
-
-bin_string([]) ->
-    [];
-bin_string([{bin_element,_,{char,_,C},_,_}|Bin]) ->
-    [C | bin_string(Bin)].
+bit_grp(Fs, Opts) ->
+    append([['<<'], [bit_elems(Fs, Opts)], ['>>']]).
 
-bit_elems(Es, Hook) ->
-    expr_list(Es, $,, fun bit_elem/2, Hook).
+bit_elems(Es, Opts) ->
+    expr_list(Es, $,, fun bit_elem/2, Opts).
 
-bit_elem({bin_element,_,Expr,Sz,Types}, Hook) ->
+bit_elem({bin_element,_,Expr,Sz,Types}, Opts) ->
     P = max_prec(),
-    VChars = lexpr(Expr, P, Hook),
+    VChars = lexpr(Expr, P, Opts),
     SChars = if
                  Sz =/= default ->
-                     [VChars,$:,lexpr(Sz, P, Hook)];
+                     [VChars,$:,lexpr(Sz, P, Opts)];
                  true ->
                      VChars
              end,
@@ -618,157 +643,157 @@ bit_elem_type(T) ->
 record_name(Name) ->
     leaf(format("#~w", [Name])).
 
-record_fields(Fs, Hook) ->
-    tuple(Fs, fun record_field/2, Hook).
+record_fields(Fs, Opts) ->
+    tuple(Fs, fun record_field/2, Opts).
 
-record_field({record_field,_,F,Val}, Hook) ->
+record_field({record_field,_,F,Val}, Opts) ->
     {L,_P,R} = inop_prec('='),
-    Fl = lexpr(F, L, Hook),
-    Vl = lexpr(Val, R, Hook),
+    Fl = lexpr(F, L, Opts),
+    Vl = lexpr(Val, R, Opts),
     {list,[{cstep,[Fl,' ='],Vl}]};
-record_field({typed_record_field,{record_field,_,F,Val},Type}, Hook) ->
+record_field({typed_record_field,{record_field,_,F,Val},Type}, Opts) ->
     {L,_P,R} = inop_prec('='),
-    Fl = lexpr(F, L, Hook),
-    Vl = typed(lexpr(Val, R, Hook), Type),
+    Fl = lexpr(F, L, Opts),
+    Vl = typed(lexpr(Val, R, Opts), Type),
     {list,[{cstep,[Fl,' ='],Vl}]};
-record_field({typed_record_field,Field,Type}, Hook) ->
-    typed(record_field(Field, Hook), Type);
-record_field({record_field,_,F}, Hook) ->
-    lexpr(F, 0, Hook).
-
-list({cons,_,H,T}, Es, Hook) ->
-    list(T, [H|Es], Hook);
-list({nil,_}, Es, Hook) ->
-    proper_list(reverse(Es), Hook);
-list(Other, Es, Hook) ->
-    improper_list(reverse(Es, [Other]), Hook).
-
-%% if_clauses(Clauses, Hook) -> [Char].
+record_field({typed_record_field,Field,Type}, Opts) ->
+    typed(record_field(Field, Opts), Type);
+record_field({record_field,_,F}, Opts) ->
+    lexpr(F, 0, Opts).
+
+list({cons,_,H,T}, Es, Opts) ->
+    list(T, [H|Es], Opts);
+list({nil,_}, Es, Opts) ->
+    proper_list(reverse(Es), Opts);
+list(Other, Es, Opts) ->
+    improper_list(reverse(Es, [Other]), Opts).
+
+%% if_clauses(Clauses, Opts) -> [Char].
 %%  Print 'if' clauses.
 
-if_clauses(Cs, Hook) ->
-    clauses(fun if_clause/2, Hook, Cs).
+if_clauses(Cs, Opts) ->
+    clauses(fun if_clause/2, Opts, Cs).
 
-if_clause({clause,_,[],G,B}, Hook) ->
-    Gl = [guard_no_when(G, Hook),' ->'],
-    {step,Gl,body(B, Hook)}.
+if_clause({clause,_,[],G,B}, Opts) ->
+    Gl = [guard_no_when(G, Opts),' ->'],
+    {step,Gl,body(B, Opts)}.
 
-guard_no_when([E|Es], Hook) when is_list(E) ->
-    expr_list([E|Es], $;, fun guard0/2, Hook);
-guard_no_when([E|Es], Hook) -> % before R6
-    guard_no_when([[E|Es]], Hook);
+guard_no_when([E|Es], Opts) when is_list(E) ->
+    expr_list([E|Es], $;, fun guard0/2, Opts);
+guard_no_when([E|Es], Opts) -> % before R6
+    guard_no_when([[E|Es]], Opts);
 guard_no_when([], _) -> % cannot happen
     leaf("true").
 
-%% cr_clauses(Clauses, Hook) -> [Char].
+%% cr_clauses(Clauses, Opts) -> [Char].
 %%  Print 'case'/'receive' clauses.
 
-cr_clauses(Cs, Hook) ->
-    clauses(fun cr_clause/2, Hook, Cs).
+cr_clauses(Cs, Opts) ->
+    clauses(fun cr_clause/2, Opts, Cs).
 
-cr_clause({clause,_,[T],G,B}, Hook) ->
-    El = lexpr(T, 0, Hook),
-    Gl = guard_when(El, G, Hook),
-    Bl = body(B, Hook),
+cr_clause({clause,_,[T],G,B}, Opts) ->
+    El = lexpr(T, 0, Opts),
+    Gl = guard_when(El, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-%% try_clauses(Clauses, Hook) -> [Char].
+%% try_clauses(Clauses, Opts) -> [Char].
 %%  Print 'try' clauses.
 
-try_clauses(Cs, Hook) ->
-    clauses(fun try_clause/2, Hook, Cs).
+try_clauses(Cs, Opts) ->
+    clauses(fun try_clause/2, Opts, Cs).
 
-try_clause({clause,_,[{tuple,_,[{atom,_,throw},V,S]}],G,B}, Hook) ->
-    El = lexpr(V, 0, Hook),
-    Sl = stack_backtrace(S, [El], Hook),
-    Gl = guard_when(Sl, G, Hook),
-    Bl = body(B, Hook),
+try_clause({clause,_,[{tuple,_,[{atom,_,throw},V,S]}],G,B}, Opts) ->
+    El = lexpr(V, 0, Opts),
+    Sl = stack_backtrace(S, [El], Opts),
+    Gl = guard_when(Sl, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl};
-try_clause({clause,_,[{tuple,_,[C,V,S]}],G,B}, Hook) ->
-    Cs = lexpr(C, 0, Hook),
-    El = lexpr(V, 0, Hook),
+try_clause({clause,_,[{tuple,_,[C,V,S]}],G,B}, Opts) ->
+    Cs = lexpr(C, 0, Opts),
+    El = lexpr(V, 0, Opts),
     CsEl = [Cs,$:,El],
-    Sl = stack_backtrace(S, CsEl, Hook),
-    Gl = guard_when(Sl, G, Hook),
-    Bl = body(B, Hook),
+    Sl = stack_backtrace(S, CsEl, Opts),
+    Gl = guard_when(Sl, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-stack_backtrace({var,_,'_'}, El, _Hook) ->
+stack_backtrace({var,_,'_'}, El, _Opts) ->
     El;
-stack_backtrace(S, El, Hook) ->
-    El++[$:,lexpr(S, 0, Hook)].
+stack_backtrace(S, El, Opts) ->
+    El++[$:,lexpr(S, 0, Opts)].
 
-%% fun_clauses(Clauses, Hook) -> [Char].
+%% fun_clauses(Clauses, Opts) -> [Char].
 %%  Print 'fun' clauses.
 
-fun_clauses(Cs, Hook) ->
-    nl_clauses(fun fun_clause/2, [$;], Hook, Cs).
+fun_clauses(Cs, Opts) ->
+    nl_clauses(fun fun_clause/2, [$;], Opts, Cs).
 
-fun_clause({clause,_,A,G,B}, Hook) ->
-    El = args(A, Hook),
-    Gl = guard_when(El, G, Hook),
-    Bl = body(B, Hook),
+fun_clause({clause,_,A,G,B}, Opts) ->
+    El = args(A, Opts),
+    Gl = guard_when(El, G, Opts),
+    Bl = body(B, Opts),
     {step,Gl,Bl}.
 
-%% cond_clauses(Clauses, Hook) -> [Char].
+%% cond_clauses(Clauses, Opts) -> [Char].
 %%  Print 'cond' clauses.
 
-cond_clauses(Cs, Hook) ->
-    clauses(fun cond_clause/2, Hook, Cs).
+cond_clauses(Cs, Opts) ->
+    clauses(fun cond_clause/2, Opts, Cs).
 
-cond_clause({clause,_,[],[[E]],B}, Hook) ->
-    {step,[lexpr(E, Hook),' ->'],body(B, Hook)}.
+cond_clause({clause,_,[],[[E]],B}, Opts) ->
+    {step,[lexpr(E, Opts),' ->'],body(B, Opts)}.
 
-%% nl_clauses(Type, Hook, Clauses) -> [Char].
+%% nl_clauses(Type, Opts, Clauses) -> [Char].
 %%  Generic clause printing function (always breaks lines).
 
-nl_clauses(Type, Sep, Hook, Cs) ->
-    {prefer_nl,Sep,lexprs(Cs, Type, Hook)}.
+nl_clauses(Type, Sep, Opts, Cs) ->
+    {prefer_nl,Sep,lexprs(Cs, Type, Opts)}.
 
-%% clauses(Type, Hook, Clauses) -> [Char].
+%% clauses(Type, Opts, Clauses) -> [Char].
 %%  Generic clause printing function (breaks lines since R12B).
 
-clauses(Type, Hook, Cs) ->
-    {prefer_nl,[$;],lexprs(Cs, Type, Hook)}.
+clauses(Type, Opts, Cs) ->
+    {prefer_nl,[$;],lexprs(Cs, Type, Opts)}.
 
-%% lc_quals(Qualifiers, After, Hook)
+%% lc_quals(Qualifiers, After, Opts)
 %% List comprehension qualifiers (breaks lines since R12B).
 
-lc_quals(Qs, Hook) ->
-    {prefer_nl,[$,],lexprs(Qs, fun lc_qual/2, Hook)}.
+lc_quals(Qs, Opts) ->
+    {prefer_nl,[$,],lexprs(Qs, fun lc_qual/2, Opts)}.
 
-lc_qual({b_generate,_,Pat,E}, Hook) ->
-    Pl = lexpr(Pat, 0, Hook),
-    {list,[{step,[Pl,leaf(" <=")],lexpr(E, 0, Hook)}]};
-lc_qual({generate,_,Pat,E}, Hook) ->
-    Pl = lexpr(Pat, 0, Hook),
-    {list,[{step,[Pl,leaf(" <-")],lexpr(E, 0, Hook)}]};
-lc_qual(Q, Hook) ->
-    lexpr(Q, 0, Hook).
+lc_qual({b_generate,_,Pat,E}, Opts) ->
+    Pl = lexpr(Pat, 0, Opts),
+    {list,[{step,[Pl,leaf(" <=")],lexpr(E, 0, Opts)}]};
+lc_qual({generate,_,Pat,E}, Opts) ->
+    Pl = lexpr(Pat, 0, Opts),
+    {list,[{step,[Pl,leaf(" <-")],lexpr(E, 0, Opts)}]};
+lc_qual(Q, Opts) ->
+    lexpr(Q, 0, Opts).
 
-proper_list(Es, Hook) ->
-    {seq,$[,$],$,,lexprs(Es, Hook)}.
+proper_list(Es, Opts) ->
+    {seq,$[,$],$,,lexprs(Es, Opts)}.
 
-improper_list(Es, Hook) ->
-    {seq,$[,$],{$,,$|},lexprs(Es, Hook)}.
+improper_list(Es, Opts) ->
+    {seq,$[,$],{$,,$|},lexprs(Es, Opts)}.
 
-tuple(L, Hook) ->
-    tuple(L, fun lexpr/2, Hook).
+tuple(L, Opts) ->
+    tuple(L, fun lexpr/2, Opts).
 
-tuple(Es, F, Hook) ->
-    {seq,${,$},$,,lexprs(Es, F, Hook)}.
+tuple(Es, F, Opts) ->
+    {seq,${,$},$,,lexprs(Es, F, Opts)}.
 
-args(As, Hook) ->
-    {seq,$(,$),[$,],lexprs(As, Hook)}.
+args(As, Opts) ->
+    {seq,$(,$),[$,],lexprs(As, Opts)}.
 
-expr_list(Es, Sep, F, Hook) ->
-    {seq,[],[],Sep,lexprs(Es, F, Hook)}.
+expr_list(Es, Sep, F, Opts) ->
+    {seq,[],[],Sep,lexprs(Es, F, Opts)}.
 
-lexprs(Es, Hook) ->
-    lexprs(Es, fun lexpr/2, Hook).
+lexprs(Es, Opts) ->
+    lexprs(Es, fun lexpr/2, Opts).
 
-lexprs(Es, F, Hook) ->
-    [F(E, Hook) || E <- Es].
+lexprs(Es, F, Opts) ->
+    [F(E, Opts) || E <- Es].
 
 maybe_paren(P, Prec, Expr) when P < Prec ->
     [$(,Expr,$)];
@@ -781,13 +806,13 @@ leaf(S) ->
 %%% Do the formatting. Currently nothing fancy. Could probably have
 %%% done it in one single pass.
 
-frmt(Item) ->
-    frmt(Item, 0).
+frmt(Item, PP) ->
+    frmt(Item, 0, PP).
 
-frmt(Item, I) ->
+frmt(Item, I, PP) ->
     ST = spacetab(),
     WT = wordtable(),
-    {Chars,_Length} = f(Item, I, ST, WT),
+    {Chars,_Length} = f(Item, I, ST, WT, PP),
     [Chars].
 
 %%% What the tags mean:
@@ -803,6 +828,7 @@ frmt(Item, I) ->
 %%% - {force_nl,ExtraInfo,I}: fun-info (a comment) forces linebreak before I.
 %%% - {prefer_nl,Sep,IPs}: forces linebreak between Is unlesss negative
 %%%   indentation.
+%%% - {char,C}: a character
 %%% - {string,S}: a string.
 %%% - {hook,...}, {ehook,...}: hook expressions.
 %%%
@@ -812,22 +838,22 @@ frmt(Item, I) ->
 %%% cstep works similarly, but no linebreak if the width of I1 is less
 %%% than the indentation (this is for "A = <expression over several lines>).
 
-f([]=Nil, _I0, _ST, _WT) ->
+f([]=Nil, _I0, _ST, _WT, _PP) ->
     {Nil,0};
-f(C, _I0, _ST, _WT) when is_integer(C) ->
+f(C, _I0, _ST, _WT, _PP) when is_integer(C) ->
     {C,1};
-f({leaf,Length,Chars}, _I0, _ST, _WT) ->
+f({leaf,Length,Chars}, _I0, _ST, _WT, _PP) ->
     {Chars,Length};
-f([Item|Items], I0, ST, WT) ->
-    consecutive(Items, f(Item, I0, ST, WT), I0, ST, WT);
-f({list,Items}, I0, ST, WT) ->
-    f({seq,[],[],[[]],Items}, I0, ST, WT);
-f({first,E,Item}, I0, ST, WT) ->
-    f({seq,E,[],[[]],[Item]}, I0, ST, WT);
-f({seq,Before,After,Sep,LItems}, I0, ST, WT) ->
-    BCharsSize = f(Before, I0, ST, WT),
+f([Item|Items], I0, ST, WT, PP) ->
+    consecutive(Items, f(Item, I0, ST, WT, PP), I0, ST, WT, PP);
+f({list,Items}, I0, ST, WT, PP) ->
+    f({seq,[],[],[[]],Items}, I0, ST, WT, PP);
+f({first,E,Item}, I0, ST, WT, PP) ->
+    f({seq,E,[],[[]],[Item]}, I0, ST, WT, PP);
+f({seq,Before,After,Sep,LItems}, I0, ST, WT, PP) ->
+    BCharsSize = f(Before, I0, ST, WT, PP),
     I = indent(BCharsSize, I0),
-    CharsSizeL = fl(LItems, Sep, I, After, ST, WT),
+    CharsSizeL = fl(LItems, Sep, I, After, ST, WT, PP),
     {CharsL,SizeL} = unz(CharsSizeL),
     {BCharsL,BSizeL} = unz1([BCharsSize]),
     Sizes = BSizeL ++ SizeL,
@@ -848,15 +874,15 @@ f({seq,Before,After,Sep,LItems}, I0, ST, WT) ->
             {BCharsL++insert_newlines(CharsSizeL, I, ST),
              nsz(lists:last(Sizes), I0)}
     end;
-f({force_nl,_ExtraInfoItem,Item}, I, ST, WT) when I < 0 ->
+f({force_nl,_ExtraInfoItem,Item}, I, ST, WT, PP) when I < 0 ->
     %% Extra info is a comment; cannot have that on the same line
-    f(Item, I, ST, WT);
-f({force_nl,ExtraInfoItem,Item}, I, ST, WT) ->
-    f({prefer_nl,[],[ExtraInfoItem,Item]}, I, ST, WT);
-f({prefer_nl,Sep,LItems}, I, ST, WT) when I < 0 ->
-    f({seq,[],[],Sep,LItems}, I, ST, WT);
-f({prefer_nl,Sep,LItems}, I0, ST, WT) ->
-    CharsSize2L = fl(LItems, Sep, I0, [], ST, WT),
+    f(Item, I, ST, WT, PP);
+f({force_nl,ExtraInfoItem,Item}, I, ST, WT, PP) ->
+    f({prefer_nl,[],[ExtraInfoItem,Item]}, I, ST, WT, PP);
+f({prefer_nl,Sep,LItems}, I, ST, WT, PP) when I < 0 ->
+    f({seq,[],[],Sep,LItems}, I, ST, WT, PP);
+f({prefer_nl,Sep,LItems}, I0, ST, WT, PP) ->
+    CharsSize2L = fl(LItems, Sep, I0, [], ST, WT, PP),
     {_CharsL,Sizes} = unz(CharsSize2L),
     if
         Sizes =:= [] ->
@@ -864,37 +890,40 @@ f({prefer_nl,Sep,LItems}, I0, ST, WT) ->
         true ->
             {insert_newlines(CharsSize2L, I0, ST),nsz(lists:last(Sizes), I0)}
     end;
-f({string,S}, I, ST, WT) ->
-    f(write_a_string(S, I), I, ST, WT);
-f({hook,HookExpr,Precedence,Func}, I, _ST, _WT) ->
-    Chars = Func(HookExpr, I, Precedence, Func),
+f({char,C}, I, ST, WT, PP) ->
+    f(write_a_char(C, PP), I, ST, WT, PP);
+f({string,S}, I, ST, WT, PP) ->
+    f(write_a_string(S, I, PP), I, ST, WT, PP);
+f({hook,HookExpr,Precedence,Func,Options}, I, _ST, _WT, _PP) ->
+    Chars = Func(HookExpr, I, Precedence, Options),
     {Chars,indentation(Chars, I)};
-f({ehook,HookExpr,Precedence,{Mod,Func,Eas}=ModFuncEas}, I, _ST, _WT) ->
+f({ehook,HookExpr,Precedence,{Mod,Func,Eas}=ModFuncEas}, I, _ST, _WT, _PP) ->
     Chars = apply(Mod, Func, [HookExpr,I,Precedence,ModFuncEas|Eas]),
     {Chars,indentation(Chars, I)};
-f(WordName, _I, _ST, WT) -> % when is_atom(WordName)
+f(WordName, _I, _ST, WT, _PP) -> % when is_atom(WordName)
     word(WordName, WT).
 
 -define(IND, 4).
 
 %% fl(ListItems, I0, ST, WT) -> [[CharsSize1,CharsSize2]]
 %% ListItems = [{Item,Items}|Item]
-fl([], _Sep, I0, After, ST, WT) ->
-    [[f(After, I0, ST, WT),{[],0}]];
-fl(CItems, Sep0, I0, After, ST, WT) ->
+fl([], _Sep, I0, After, ST, WT, PP) ->
+    [[f(After, I0, ST, WT, PP),{[],0}]];
+fl(CItems, Sep0, I0, After, ST, WT, PP) ->
     F = fun({step,Item1,Item2}, S) ->
-                [f(Item1, I0, ST, WT),f([Item2,S], incr(I0, ?IND), ST, WT)];
+                [f(Item1, I0, ST, WT, PP),
+                 f([Item2,S], incr(I0, ?IND), ST, WT, PP)];
            ({cstep,Item1,Item2}, S) ->
-                {_,Sz1} = CharSize1 = f(Item1, I0, ST, WT),
+                {_,Sz1} = CharSize1 = f(Item1, I0, ST, WT, PP),
                 if
                     is_integer(Sz1), Sz1 < ?IND ->
                         Item2p = [leaf("\s"),Item2,S],
-                        [consecutive(Item2p, CharSize1, I0, ST, WT),{[],0}];
+                        [consecutive(Item2p, CharSize1, I0, ST, WT, PP),{[],0}];
                     true ->
-                        [CharSize1,f([Item2,S], incr(I0, ?IND), ST, WT)]
+                        [CharSize1,f([Item2,S], incr(I0, ?IND), ST, WT, PP)]
                 end;
            (Item, S) ->
-                [f([Item,S], I0, ST, WT),{[],0}]
+                [f([Item,S], I0, ST, WT, PP),{[],0}]
         end,
     {Sep,LastSep}  = case Sep0 of {_,_} -> Sep0; _ -> {Sep0,Sep0} end,
     fl1(CItems, F, Sep, LastSep, After).
@@ -906,10 +935,10 @@ fl1([CItem1,CItem2], F, _Sep, LastSep, After) ->
 fl1([CItem|CItems], F, Sep, LastSep, After) ->
     [F(CItem, Sep)|fl1(CItems, F, Sep, LastSep, After)].
 
-consecutive(Items, CharSize1, I0, ST, WT) ->
+consecutive(Items, CharSize1, I0, ST, WT, PP) ->
     {CharsSizes,_Length} =
         mapfoldl(fun(Item, Len) ->
-                         CharsSize = f(Item, Len, ST, WT),
+                         CharsSize = f(Item, Len, ST, WT, PP),
                          {CharsSize,indent(CharsSize, Len)}
                  end, indent(CharSize1, I0), Items),
     {CharsL,SizeL} = unz1([CharSize1|CharsSizes]),
@@ -999,26 +1028,40 @@ has_nl([C|Cs]) ->
 has_nl([]) ->
     false.
 
+write_a_char(C, PP) ->
+    flat_leaf(write_char(C, PP)).
+
 -define(MIN_SUBSTRING, 5).
 
-write_a_string(S, I) when I < 0; S =:= [] ->
-    leaf(write_string(S));
-write_a_string(S, I) ->
+write_a_string(S, I, PP) when I < 0; S =:= [] ->
+    flat_leaf(write_string(S, PP));
+write_a_string(S, I, PP) ->
     Len = erlang:max(?MAXLINE-I, ?MIN_SUBSTRING),
-    {list,write_a_string(S, Len, Len)}.
+    {list,write_a_string(S, Len, Len, PP)}.
 
-write_a_string([], _N, _Len) ->
+write_a_string([], _N, _Len, _PP) ->
     [];
-write_a_string(S, N, Len) ->
+write_a_string(S, N, Len, PP) ->
     SS = string:sub_string(S, 1, N),
-    Sl = write_string(SS),
-    case (iolist_size(Sl) > Len) and (N > ?MIN_SUBSTRING) of
+    Sl = write_string(SS, PP),
+    case (length(Sl) > Len) and (N > ?MIN_SUBSTRING) of
         true ->
-            write_a_string(S, N-1, Len);
+            write_a_string(S, N-1, Len, PP);
         false ->
-            [leaf(Sl)|write_a_string(lists:nthtail(length(SS), S), Len, Len)]
+            [flat_leaf(Sl) |
+             write_a_string(lists:nthtail(length(SS), S), Len, Len, PP)]
     end.
 
+flat_leaf(S) ->
+    L = lists:flatten(S),
+    {leaf,length(L),L}.
+
+write_string(S, PP) ->
+    lists:flatten((PP#pp.string_fun)(S)).
+
+write_char(C, PP) ->
+    lists:flatten((PP#pp.char_fun)(C)).
+
 %%
 %% Utilities
 %%