Complete support of maps in erl_syntax

	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

1 files changed, 231 insertions, 26 deletions

diff --git a/lib/syntax_tools/src/erl_syntax.erl b/lib/syntax_tools/src/erl_syntax.erl
index 93187fa018..2f4c9ac309 100644
--- a/lib/syntax_tools/src/erl_syntax.erl
+++ b/lib/syntax_tools/src/erl_syntax.erl
@@ -220,6 +220,16 @@
 	 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,
@@ -580,11 +590,12 @@ 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;
-	{map,_,_} -> map;
-	{map_field_assoc,_,_,_} -> map_field_assoc;
-	{map_field_exact,_,_,_} -> map_field_exact;
 	{record, _, _, _, _} -> record_expr;
 	{record, _, _, _} -> record_expr;
 	{record_field, _, _, _, _} -> record_access;
@@ -1913,26 +1924,206 @@ atom_literal(Node) ->
 
 
 %% =====================================================================
+%% @equiv map_expr(none, Fields)
 
-map_elements(Node) ->
+-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, _, List} ->
-	    List;
-	Node1 ->
-	    data(Node1)
+        {map, _, _} ->
+            none;
+        {map, _, Argument, _} ->
+            Argument;
+        Node1 ->
+            (data(Node1))#map_expr.argument
     end.
 
-map_field_elements({_,_,K,V}) ->
-    [K,V].
 
-map(List) ->
-    tree(map, List).
+%% =====================================================================
+%% @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.
+
 
-map_field_assoc(List) ->
-    tree(map_field_assoc, List).
+%% =====================================================================
+%% @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.
 
-map_field_exact(List) ->
-    tree(map_field_exact, List).
 
 %% =====================================================================
 %% @doc Creates an abstract tuple. If `Elements' is
@@ -6117,6 +6308,12 @@ 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 ->
@@ -6358,6 +6555,19 @@ 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)]];
@@ -6421,12 +6631,6 @@ subtrees(T) ->
 		     try_expr_clauses(T),
 		     try_expr_handlers(T),
 		     try_expr_after(T)];
-	        map ->
-		    [map_elements(T)];
-		map_field_assoc ->
-		    [map_field_elements(T)];
-		map_field_exact ->
-		    [map_field_elements(T)];
 		tuple ->
 		    [tuple_elements(T)]
 	    end
@@ -6502,6 +6706,10 @@ 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);
@@ -6522,10 +6730,7 @@ make_tree(record_index_expr, [[T], [F]]) ->
 make_tree(rule, [[N], C]) -> rule(N, C);
 make_tree(size_qualifier, [[N], [A]]) -> size_qualifier(N, A);
 make_tree(try_expr, [B, C, H, A]) -> try_expr(B, C, H, A);
-make_tree(tuple, [E]) -> tuple(E);
-make_tree(map, [E]) -> map(E);
-make_tree(map_field_assoc, [E]) -> map_field_assoc(E);
-make_tree(map_field_exact, [E]) -> map_field_exact(E).
+make_tree(tuple, [E]) -> tuple(E).
 
 
 %% =====================================================================