3 files changed, 415 insertions, 7 deletions

diff --git a/lib/syntax_tools/src/erl_prettypr.erl b/lib/syntax_tools/src/erl_prettypr.erl
index 1ffcf31134..877675772f 100644
--- a/lib/syntax_tools/src/erl_prettypr.erl
+++ b/lib/syntax_tools/src/erl_prettypr.erl
@@ -637,6 +637,14 @@ lay_2(Node, Ctxt) ->
 	    sep([follow(text("fun"), D, Ctxt1#ctxt.sub_indent),
 		 text("end")]);
 
+        named_fun_expr ->
+            Ctxt1 = reset_prec(Ctxt),
+            D1 = lay(erl_syntax:named_fun_expr_name(Node), Ctxt1),
+            D = lay_clauses(erl_syntax:named_fun_expr_clauses(Node),
+                            {function,D1}, Ctxt1),
+            sep([follow(text("fun"), D, Ctxt1#ctxt.sub_indent),
+                 text("end")]);
+
 	module_qualifier ->
 	    {PrecL, _Prec, PrecR} = inop_prec(':'),
 	    D1 = lay(erl_syntax:module_qualifier_argument(Node),
@@ -892,6 +900,32 @@ lay_2(Node, Ctxt) ->
 			beside(floating(text(".")), D2)),
 	    maybe_parentheses(D3, Prec, Ctxt);
 
+        map_expr ->
+            {PrecL, Prec, _} = inop_prec('#'),
+            Ctxt1 = reset_prec(Ctxt),
+            D1 = par(seq(erl_syntax:map_expr_fields(Node),
+                         floating(text(",")), Ctxt1, fun lay/2)),
+            D2 = beside(text("#{"), beside(D1, floating(text("}")))),
+            D3 = case erl_syntax:map_expr_argument(Node) of
+                         none ->
+                             D2;
+                         A ->
+                             beside(lay(A, set_prec(Ctxt, PrecL)), D2)
+                 end,
+            maybe_parentheses(D3, Prec, Ctxt);
+
+        map_field_assoc ->
+            Ctxt1 = reset_prec(Ctxt),
+            D1 = lay(erl_syntax:map_field_assoc_name(Node), Ctxt1),
+            D2 = lay(erl_syntax:map_field_assoc_value(Node), Ctxt1),
+            par([D1, floating(text("=>")), D2], Ctxt1#ctxt.break_indent);
+
+        map_field_exact ->
+            Ctxt1 = reset_prec(Ctxt),
+            D1 = lay(erl_syntax:map_field_exact_name(Node), Ctxt1),
+            D2 = lay(erl_syntax:map_field_exact_value(Node), Ctxt1),
+            par([D1, floating(text(":=")), D2], Ctxt1#ctxt.break_indent);
+
 	rule ->
 	    %% Comments on the name will be repeated; cf.
 	    %% `function'.
diff --git a/lib/syntax_tools/src/erl_syntax.erl b/lib/syntax_tools/src/erl_syntax.erl
index 775b2cc109..2f4c9ac309 100644
--- a/lib/syntax_tools/src/erl_syntax.erl
+++ b/lib/syntax_tools/src/erl_syntax.erl
@@ -220,12 +220,26 @@
 	 macro/2,
 	 macro_arguments/1,
 	 macro_name/1,
+         map_expr/1,
+         map_expr/2,
+         map_expr_argument/1,
+         map_expr_fields/1,
+         map_field_assoc/2,
+         map_field_assoc_name/1,
+         map_field_assoc_value/1,
+         map_field_exact/2,
+         map_field_exact_name/1,
+         map_field_exact_value/1,
 	 match_expr/2,
 	 match_expr_body/1,
 	 match_expr_pattern/1,
 	 module_qualifier/2,
 	 module_qualifier_argument/1,
 	 module_qualifier_body/1,
+	 named_fun_expr/2,
+	 named_fun_expr_arity/1,
+	 named_fun_expr_clauses/1,
+	 named_fun_expr_name/1,
 	 nil/0,
 	 operator/1,
 	 operator_literal/1,
@@ -442,28 +456,30 @@
 %%   <td>match_expr</td>
 %%   <td>module_qualifier</td>
 %%  </tr><tr>
+%%   <td>named_fun_expr</td>
 %%   <td>nil</td>
 %%   <td>operator</td>
 %%   <td>parentheses</td>
-%%   <td>prefix_expr</td>
 %%  </tr><tr>
+%%   <td>prefix_expr</td>
 %%   <td>receive_expr</td>
 %%   <td>record_access</td>
-%%  </tr><tr>
 %%   <td>record_expr</td>
+%%  </tr><tr>
 %%   <td>record_field</td>
 %%   <td>record_index_expr</td>
 %%   <td>rule</td>
-%%  </tr><tr>
 %%   <td>size_qualifier</td>
+%%  </tr><tr>
 %%   <td>string</td>
 %%   <td>text</td>
 %%   <td>try_expr</td>
-%%  </tr><tr>
 %%   <td>tuple</td>
+%%  </tr><tr>
 %%   <td>underscore</td>
 %%   <td>variable</td>
 %%   <td>warning_marker</td>
+%%   <td></td>
 %%  </tr>
 %% </table></center>
 %%
@@ -506,6 +522,7 @@
 %% @see macro/2
 %% @see match_expr/2
 %% @see module_qualifier/2
+%% @see named_fun_expr/2
 %% @see nil/0
 %% @see operator/1
 %% @see parentheses/1
@@ -554,6 +571,7 @@ type(Node) ->
 	{'catch', _, _} -> catch_expr;
 	{'cond', _, _} -> cond_expr;
 	{'fun', _, {clauses, _}} -> fun_expr;
+	{named_fun, _, _, _} -> named_fun_expr;
 	{'fun', _, {function, _, _}} -> implicit_fun;
 	{'fun', _, {function, _, _, _}} -> implicit_fun;
 	{'if', _, _} -> if_expr;
@@ -572,6 +590,10 @@ type(Node) ->
 	{lc, _, _, _} -> list_comp;
 	{bc, _, _, _} -> binary_comp;		
 	{match, _, _, _} -> match_expr;
+        {map, _, _, _} -> map_expr;
+        {map, _, _} -> map_expr;
+        {map_field_assoc, _, _, _} -> map_field_assoc;
+        {map_field_exact, _, _, _} -> map_field_exact;
 	{op, _, _, _, _} -> infix_expr;
 	{op, _, _, _} -> prefix_expr;
 	{record, _, _, _, _} -> record_expr;
@@ -1902,6 +1924,208 @@ atom_literal(Node) ->
 
 
 %% =====================================================================
+%% @equiv map_expr(none, Fields)
+
+-spec map_expr([syntaxTree()]) -> syntaxTree().
+
+map_expr(Fields) ->
+    map_expr(none, Fields).
+
+
+%% =====================================================================
+%% @doc Creates an abstract map expression. If `Fields' is
+%% `[F1, ..., Fn]', then if `Argument' is `none', the result represents
+%% "<code>#{<em>F1</em>, ..., <em>Fn</em>}</code>",
+%% otherwise it represents
+%% "<code><em>Argument</em>#{<em>F1</em>, ..., <em>Fn</em>}</code>".
+%%
+%% @see map_expr/1
+%% @see map_expr_argument/1
+%% @see map_expr_fields/1
+%% @see map_field_assoc/2
+%% @see map_field_exact/2
+
+-record(map_expr, {argument :: 'none' | syntaxTree(),
+                   fields   :: [syntaxTree()]}).
+
+%% `erl_parse' representation:
+%%
+%% {map, Pos, Fields}
+%% {map, Pos, Argument, Fields}
+
+-spec map_expr('none' | syntaxTree(), [syntaxTree()]) -> syntaxTree().
+
+map_expr(Argument, Fields) ->
+    tree(map_expr, #map_expr{argument = Argument, fields = Fields}).
+
+revert_map_expr(Node) ->
+    Pos = get_pos(Node),
+    Argument = map_expr_argument(Node),
+    Fields = map_expr_fields(Node),
+    case Argument of
+        none ->
+            {map, Pos, Fields};
+        _ ->
+            {map, Pos, Argument, Fields}
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the argument subtree of a `map_expr' node, if any. If `Node'
+%% represents "<code>#{...}</code>", `none' is returned.
+%% Otherwise, if `Node' represents "<code><em>Argument</em>#{...}</code>",
+%% `Argument' is returned.
+%%
+%% @see map_expr/3
+
+-spec map_expr_argument(syntaxTree()) -> 'none' | syntaxTree().
+
+map_expr_argument(Node) ->
+    case unwrap(Node) of
+        {map, _, _} ->
+            none;
+        {map, _, Argument, _} ->
+            Argument;
+        Node1 ->
+            (data(Node1))#map_expr.argument
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the list of field subtrees of a `map_expr' node.
+%%
+%% @see map_expr/3
+
+-spec map_expr_fields(syntaxTree()) -> [syntaxTree()].
+
+map_expr_fields(Node) ->
+    case unwrap(Node) of
+        {map, _, Fields} ->
+            Fields;
+        {map, _, _, Fields} ->
+            Fields;
+        Node1 ->
+            (data(Node1))#map_expr.fields
+    end.
+
+
+%% =====================================================================
+%% @doc Creates an abstract map assoc field. The result represents
+%% "<code><em>Name</em> => <em>Value</em></code>".
+%%
+%% @see map_field_assoc_name/1
+%% @see map_field_assoc_value/1
+%% @see map_expr/3
+
+-record(map_field_assoc, {name :: syntaxTree(), value :: syntaxTree()}).
+
+%% `erl_parse' representation:
+%%
+%% {map_field_assoc, Pos, Name, Value}
+
+-spec map_field_assoc(syntaxTree(), syntaxTree()) -> syntaxTree().
+
+map_field_assoc(Name, Value) ->
+    tree(map_field_assoc, #map_field_assoc{name = Name, value = Value}).
+
+revert_map_field_assoc(Node) ->
+    Pos = get_pos(Node),
+    Name = map_field_assoc_name(Node),
+    Value = map_field_assoc_value(Node),
+    {map_field_assoc, Pos, Name, Value}.
+
+
+%% =====================================================================
+%% @doc Returns the name subtree of a `map_field_assoc' node.
+%%
+%% @see map_field_assoc/2
+
+-spec map_field_assoc_name(syntaxTree()) -> syntaxTree().
+
+map_field_assoc_name(Node) ->
+    case Node of
+        {map_field_assoc, _, Name, _} ->
+            Name;
+        _ ->
+            (data(Node))#map_field_assoc.name
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the value subtree of a `map_field_assoc' node.
+%%
+%% @see map_field_assoc/2
+
+-spec map_field_assoc_value(syntaxTree()) -> syntaxTree().
+
+map_field_assoc_value(Node) ->
+    case Node of
+        {map_field_assoc, _, _, Value} ->
+            Value;
+        _ ->
+            (data(Node))#map_field_assoc.name
+    end.
+
+
+%% =====================================================================
+%% @doc Creates an abstract map exact field. The result represents
+%% "<code><em>Name</em> := <em>Value</em></code>".
+%%
+%% @see map_field_exact_name/1
+%% @see map_field_exact_value/1
+%% @see map_expr/3
+
+-record(map_field_exact, {name :: syntaxTree(), value :: syntaxTree()}).
+
+%% `erl_parse' representation:
+%%
+%% {map_field_exact, Pos, Name, Value}
+
+-spec map_field_exact(syntaxTree(), syntaxTree()) -> syntaxTree().
+
+map_field_exact(Name, Value) ->
+    tree(map_field_exact, #map_field_exact{name = Name, value = Value}).
+
+revert_map_field_exact(Node) ->
+    Pos = get_pos(Node),
+    Name = map_field_exact_name(Node),
+    Value = map_field_exact_value(Node),
+    {map_field_exact, Pos, Name, Value}.
+
+
+%% =====================================================================
+%% @doc Returns the name subtree of a `map_field_exact' node.
+%%
+%% @see map_field_exact/2
+
+-spec map_field_exact_name(syntaxTree()) -> syntaxTree().
+
+map_field_exact_name(Node) ->
+    case Node of
+        {map_field_exact, _, Name, _} ->
+            Name;
+        _ ->
+            (data(Node))#map_field_exact.name
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the value subtree of a `map_field_exact' node.
+%%
+%% @see map_field_exact/2
+
+-spec map_field_exact_value(syntaxTree()) -> syntaxTree().
+
+map_field_exact_value(Node) ->
+    case Node of
+        {map_field_exact, _, _, Value} ->
+            Value;
+        _ ->
+            (data(Node))#map_field_exact.name
+    end.
+
+
+%% =====================================================================
 %% @doc Creates an abstract tuple. If `Elements' is
 %% `[X1, ..., Xn]', the result represents
 %% "<code>{<em>X1</em>, ..., <em>Xn</em>}</code>".
@@ -5622,6 +5846,110 @@ fun_expr_arity(Node) ->
 
 
 %% =====================================================================
+%% @doc Creates an abstract named fun-expression. If `Clauses' is
+%% `[C1, ..., Cn]', the result represents "<code>fun
+%% <em>Name</em> <em>C1</em>; ...; <em>Name</em> <em>Cn</em> end</code>".
+%% More exactly, if each `Ci' represents
+%% "<code>(<em>Pi1</em>, ..., <em>Pim</em>) <em>Gi</em> -> <em>Bi</em></code>",
+%% then the result represents
+%% "<code>fun <em>Name</em>(<em>P11</em>, ..., <em>P1m</em>) <em>G1</em> ->
+%% <em>B1</em>; ...; <em>Name</em>(<em>Pn1</em>, ..., <em>Pnm</em>)
+%% <em>Gn</em> -> <em>Bn</em> end</code>".
+%%
+%% @see named_fun_expr_name/1
+%% @see named_fun_expr_clauses/1
+%% @see named_fun_expr_arity/1
+
+-record(named_fun_expr, {name :: syntaxTree(), clauses :: [syntaxTree()]}).
+
+%% type(Node) = named_fun_expr
+%% data(Node) = #named_fun_expr{name :: Name, clauses :: Clauses}
+%%
+%%	Name = syntaxTree()
+%%	Clauses = [syntaxTree()]
+%%
+%%	(See `function' for notes; e.g. why the arity is not stored.)
+%%
+%% `erl_parse' representation:
+%%
+%% {named_fun, Pos, Name, Clauses}
+%%
+%%	Clauses = [Clause] \ []
+%%	Clause = {clause, ...}
+%%
+%%	See `clause' for documentation on `erl_parse' clauses.
+
+-spec named_fun_expr(syntaxTree(), [syntaxTree()]) -> syntaxTree().
+
+named_fun_expr(Name, Clauses) ->
+    tree(named_fun_expr, #named_fun_expr{name = Name, clauses = Clauses}).
+
+revert_named_fun_expr(Node) ->
+    Pos = get_pos(Node),
+    Name = named_fun_expr_name(Node),
+    Clauses = [revert_clause(C) || C <- named_fun_expr_clauses(Node)],
+    case type(Name) of
+	variable ->
+	    {named_fun, Pos, variable_name(Name), Clauses};
+	_ ->
+	    Node
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the name subtree of a `named_fun_expr' node.
+%%
+%% @see named_fun_expr/2
+
+-spec named_fun_expr_name(syntaxTree()) -> syntaxTree().
+
+named_fun_expr_name(Node) ->
+    case unwrap(Node) of
+	{named_fun, Pos, Name, _} ->
+	    set_pos(variable(Name), Pos);
+	Node1 ->
+	    (data(Node1))#named_fun_expr.name
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the list of clause subtrees of a `named_fun_expr' node.
+%%
+%% @see named_fun_expr/2
+
+-spec named_fun_expr_clauses(syntaxTree()) -> [syntaxTree()].
+
+named_fun_expr_clauses(Node) ->
+    case unwrap(Node) of
+	{named_fun, _, _, Clauses} ->
+	    Clauses;
+	Node1 ->
+	    (data(Node1))#named_fun_expr.clauses
+    end.
+
+
+%% =====================================================================
+%% @doc Returns the arity of a `named_fun_expr' node. The result is
+%% the number of parameter patterns in the first clause of the
+%% named fun-expression; subsequent clauses are ignored.
+%%
+%% An exception is thrown if `named_fun_expr_clauses(Node)'
+%% returns an empty list, or if the first element of that list is not a
+%% syntax tree `C' of type `clause' such that
+%% `clause_patterns(C)' is a nonempty list.
+%%
+%% @see named_fun_expr/2
+%% @see named_fun_expr_clauses/1
+%% @see clause/3
+%% @see clause_patterns/1
+
+-spec named_fun_expr_arity(syntaxTree()) -> arity().
+
+named_fun_expr_arity(Node) ->
+    length(clause_patterns(hd(named_fun_expr_clauses(Node)))).
+
+
+%% =====================================================================
 %% @doc Creates an abstract parenthesised expression. The result
 %% represents "<code>(<em>Body</em>)</code>", independently of the
 %% context.
@@ -5980,10 +6308,18 @@ revert_root(Node) ->
 	    revert_list(Node);
 	list_comp ->
 	    revert_list_comp(Node);
+        map_expr ->
+            revert_map_expr(Node);
+        map_field_assoc ->
+            revert_map_field_assoc(Node);
+        map_field_exact ->
+            revert_map_field_exact(Node);
 	match_expr ->
 	    revert_match_expr(Node);
 	module_qualifier ->
 	    revert_module_qualifier(Node);
+	named_fun_expr ->
+	    revert_named_fun_expr(Node);
 	nil ->
 	    revert_nil(Node);
 	parentheses ->
@@ -6219,12 +6555,28 @@ subtrees(T) ->
 			As ->
 			    [[macro_name(T)], As]
 		    end;
+                map_expr ->
+                    case map_expr_argument(T) of
+                        none ->
+                            [map_expr_fields(T)];
+                        V ->
+                            [[V], map_expr_fields(T)]
+                    end;
+                map_field_assoc ->
+                    [[map_field_assoc_name(T)],
+                     [map_field_assoc_value(T)]];
+                map_field_exact ->
+                    [[map_field_exact_name(T)],
+                     [map_field_exact_value(T)]];
 		match_expr ->
 		    [[match_expr_pattern(T)],
 		     [match_expr_body(T)]];
 		module_qualifier ->
 		    [[module_qualifier_argument(T)],
 		     [module_qualifier_body(T)]];
+		named_fun_expr ->
+			[[named_fun_expr_name(T)],
+			 named_fun_expr_clauses(T)];
 		parentheses ->
 		    [[parentheses_body(T)]];
 		prefix_expr ->
@@ -6354,7 +6706,12 @@ make_tree(list, [P, [S]]) -> list(P, S);
 make_tree(list_comp, [[T], B]) -> list_comp(T, B);
 make_tree(macro, [[N]]) -> macro(N);
 make_tree(macro, [[N], A]) -> macro(N, A);
+make_tree(map_expr, [Fs]) -> map_expr(Fs);
+make_tree(map_expr, [[E], Fs]) -> map_expr(E, Fs);
+make_tree(map_field_assoc, [[K], [V]]) -> map_field_assoc(K, V);
+make_tree(map_field_exact, [[K], [V]]) -> map_field_exact(K, V);
 make_tree(match_expr, [[P], [E]]) -> match_expr(P, E);
+make_tree(named_fun_expr, [[N], C]) -> named_fun_expr(N, C);
 make_tree(module_qualifier, [[M], [N]]) -> module_qualifier(M, N);
 make_tree(parentheses, [[E]]) -> parentheses(E);
 make_tree(prefix_expr, [[F], [A]]) -> prefix_expr(F, A);
diff --git a/lib/syntax_tools/src/erl_tidy.erl b/lib/syntax_tools/src/erl_tidy.erl
index 0c149634f6..7444d8dc67 100644
--- a/lib/syntax_tools/src/erl_tidy.erl
+++ b/lib/syntax_tools/src/erl_tidy.erl
@@ -269,6 +269,13 @@ file(Name) ->
 %%       is typically most useful if the `verbose' flag is enabled, to
 %%       generate reports about the program files without affecting
 %%       them. The default value is `false'.</dd>
+%%
+%%   <dt>{stdout, boolean()}</dt>
+%%
+%%      <dd>If the value is `true', instead of the file being written
+%%      to disk it will be printed to stdout. The default value is
+%%      `false'.</dd>
+%%
 %% </dl>
 %%
 %% See the function `module/2' for further options.
@@ -309,9 +316,15 @@ file_2(Name, Opts) ->
         true ->
             ok;
         false ->
-            write_module(Tree, Name, Opts1),
-            ok
-    end.
+			case proplists:get_bool(stdout, Opts1) of
+				true ->
+					print_module(Tree, Opts1),
+					ok;
+				false ->
+					write_module(Tree, Name, Opts1),
+					ok
+			end
+	end.
 
 read_module(Name, Opts) ->
     verbose("reading module `~ts'.", [filename(Name)], Opts),
@@ -399,6 +412,10 @@ write_module(Tree, Name, Opts) ->
             throw(R)
     end.
 
+print_module(Tree, Opts) ->
+	Printer = proplists:get_value(printer, Opts),
+	io:format(Printer(Tree, Opts)).
+
 output(FD, Printer, Tree, Opts) ->
     io:put_chars(FD, Printer(Tree, Opts)),
     io:nl(FD).