Make the syntax for map pairs readable

Use the same syntax for map pairs in Core Erlang code as in the
Erlang Code. This Erlang code:

  M#{x:=42,y=>1}

will look like this in Core Erlang:

  ~{'x':=42,'y'=>1|M}~

4 files changed, 23 insertions, 25 deletions

diff --git a/lib/compiler/src/core_parse.yrl b/lib/compiler/src/core_parse.yrl
index 849f801a11..8bdb6bc37d 100644
--- a/lib/compiler/src/core_parse.yrl
+++ b/lib/compiler/src/core_parse.yrl
@@ -58,7 +58,8 @@ Terminals
 
 %% Separators
 
-'(' ')' '{' '}' '[' ']' '|' ',' '->' '=' '/' '<' '>' ':' '-|' '#' '~' '::'
+'(' ')' '{' '}' '[' ']' '|' ',' '->' '=' '/' '<' '>' ':' '-|' '#'
+'~' '=>' ':='
 
 %% Keywords (atoms are assumed to always be single-quoted).
 
@@ -189,8 +190,9 @@ map_pattern -> '~' '{' map_pair_patterns '}' '~' :
 map_pair_patterns -> map_pair_pattern : ['$1'].
 map_pair_patterns -> map_pair_pattern ',' map_pair_patterns : ['$1' | '$3'].
 
-map_pair_pattern -> '~' '<' anno_expression ',' anno_pattern '>' :
-			#c_map_pair{op=#c_literal{val=exact},key='$3',val='$5'}.
+map_pair_pattern -> anno_expression ':=' anno_pattern :
+			#c_map_pair{op=#c_literal{val=exact},
+				    key='$1',val='$3'}.
 
 cons_pattern -> '[' anno_pattern tail_pattern :
 		    c_cons('$2', '$3').
@@ -295,10 +297,10 @@ map_pairs -> map_pair ',' map_pairs : ['$1' | '$3'].
 map_pair -> map_pair_assoc : '$1'.
 map_pair -> map_pair_exact : '$1'.
 
-map_pair_assoc -> '::' '<' anno_expression ',' anno_expression'>' :
-		#c_map_pair{op=#c_literal{val=assoc},key='$3',val='$5'}.
-map_pair_exact -> '~' '<' anno_expression ',' anno_expression'>' :
-		#c_map_pair{op=#c_literal{val=exact},key='$3',val='$5'}.
+map_pair_assoc -> anno_expression '=>' anno_expression :
+		#c_map_pair{op=#c_literal{val=assoc},key='$1',val='$3'}.
+map_pair_exact -> anno_expression ':=' anno_expression :
+		#c_map_pair{op=#c_literal{val=exact},key='$1',val='$3'}.
 
 cons -> '[' anno_expression tail : c_cons('$2', '$3').
 
diff --git a/lib/compiler/src/core_pp.erl b/lib/compiler/src/core_pp.erl
index 01922c3fdf..662ef6c83f 100644
--- a/lib/compiler/src/core_pp.erl
+++ b/lib/compiler/src/core_pp.erl
@@ -183,15 +183,9 @@ format_1(#c_map{arg=Var,es=Es}, Ctxt) ->
      "}~"
     ];
 format_1(#c_map_pair{op=#c_literal{val=assoc},key=K,val=V}, Ctxt) ->
-    ["::<",
-     format_map_pair(K, V, Ctxt),
-     ">"
-    ];
+    format_map_pair("=>", K, V, Ctxt);
 format_1(#c_map_pair{op=#c_literal{val=exact},key=K,val=V}, Ctxt) ->
-    ["~<",
-     format_map_pair(K, V, Ctxt),
-     ">"
-    ];
+    format_map_pair(":=", K, V, Ctxt);
 format_1(#c_cons{hd=H,tl=T}, Ctxt) ->
     Txt = ["["|format(H, add_indent(Ctxt, 1))],
     [Txt|format_list_tail(T, add_indent(Ctxt, width(Txt, Ctxt)))];
@@ -448,11 +442,11 @@ format_list_tail(#c_cons{anno=[],hd=H,tl=T}, Ctxt) ->
 format_list_tail(Tail, Ctxt) ->
     ["|",format(Tail, add_indent(Ctxt, 1)),"]"].
 
-format_map_pair(K, V, Ctxt0) ->
+format_map_pair(Op, K, V, Ctxt0) ->
     Ctxt1 = add_indent(Ctxt0, 1),
     Txt = format(K, set_class(Ctxt1, expr)),
     Ctxt2 = add_indent(Ctxt0, width(Txt, Ctxt1)),
-    [Txt,",",format(V, Ctxt2)].
+    [Txt,Op,format(V, Ctxt2)].
 
 indent(Ctxt) -> indent(Ctxt#ctxt.indent, Ctxt).
 
diff --git a/lib/compiler/src/core_scan.erl b/lib/compiler/src/core_scan.erl
index b7799b373a..8ab20b1982 100644
--- a/lib/compiler/src/core_scan.erl
+++ b/lib/compiler/src/core_scan.erl
@@ -271,8 +271,10 @@ scan1("->" ++ Cs, Toks, Pos) ->
     scan1(Cs, [{'->',Pos}|Toks], Pos);
 scan1("-|" ++ Cs, Toks, Pos) ->
     scan1(Cs, [{'-|',Pos}|Toks], Pos);
-scan1("::" ++ Cs, Toks, Pos) ->
-    scan1(Cs, [{'::',Pos}|Toks], Pos);
+scan1(":=" ++ Cs, Toks, Pos) ->
+    scan1(Cs, [{':=',Pos}|Toks], Pos);
+scan1("=>" ++ Cs, Toks, Pos) ->
+    scan1(Cs, [{'=>',Pos}|Toks], Pos);
 scan1([C|Cs], Toks, Pos) ->				%Punctuation character
     P = list_to_atom([C]),
     scan1(Cs, [{P,Pos}|Toks], Pos);
diff --git a/lib/compiler/test/core_SUITE_data/map_core_test.core b/lib/compiler/test/core_SUITE_data/map_core_test.core
index 2aa853d450..a75f6cf24f 100644
--- a/lib/compiler/test/core_SUITE_data/map_core_test.core
+++ b/lib/compiler/test/core_SUITE_data/map_core_test.core
@@ -7,11 +7,11 @@ module 'map_core_test' ['map_core_test'/0,
     fun () ->
 	let <_cor0> =
 	    %% Line 15
-	    ~{::<'check','ok'>,::<1337,#{#<104>(8,1,'integer',['unsigned'|['big']]),
+	    ~{'check'=>'ok',1337=>#{#<104>(8,1,'integer',['unsigned'|['big']]),
 				      #<101>(8,1,'integer',['unsigned'|['big']]),
 				      #<108>(8,1,'integer',['unsigned'|['big']]),
 				      #<108>(8,1,'integer',['unsigned'|['big']]),
-				      #<111>(8,1,'integer',['unsigned'|['big']])}#>,::<'val',0>}~
+				      #<111>(8,1,'integer',['unsigned'|['big']])}#,'val'=>0}~
 	in  let <M> =
 		%% Line 15
 		apply 'id'/1
@@ -23,7 +23,7 @@ module 'map_core_test' ['map_core_test'/0,
 		in  %% Line 16
 		    case apply 'call'/2
 			     (M, _cor2) of
-		      <~{~<1337,#{#<104>(8,1,'integer',['unsigned'|['big']]),
+		      <~{1337:=#{#<104>(8,1,'integer',['unsigned'|['big']]),
 				#<101>(8,1,'integer',['unsigned'|['big']]),
 				#<108>(8,1,'integer',['unsigned'|['big']]),
 				#<108>(8,1,'integer',['unsigned'|['big']]),
@@ -39,7 +39,7 @@ module 'map_core_test' ['map_core_test'/0,
 				#<32>(8,1,'integer',['unsigned'|['big']]),
 				#<53>(8,1,'integer',['unsigned'|['big']]),
 				#<32>(8,1,'integer',['unsigned'|['big']]),
-				#<54>(8,1,'integer',['unsigned'|['big']])}#>,~<'check','ok'>,~<'val',21>}~> when 'true' ->
+				#<54>(8,1,'integer',['unsigned'|['big']])}#,'check':='ok','val':=21}~> when 'true' ->
 			  %% Line 17
 			  'ok'
 		      ( <_cor3> when 'true' ->
@@ -51,7 +51,7 @@ module 'map_core_test' ['map_core_test'/0,
     %% Line 20
     fun (_cor1,_cor0) ->
 	case <_cor1,_cor0> of
-	  <M = ~{~<1337,Bin>,~<'check',_cor8>,~<'val',Val>}~,[V|Vs]> when 'true' ->
+	  <M = ~{1337:=Bin,'check':=_cor8,'val':=Val}~,[V|Vs]> when 'true' ->
 	      let <_cor3> =
 		  %% Line 21
 		  call 'erlang':'+'
@@ -67,7 +67,7 @@ module 'map_core_test' ['map_core_test'/0,
 			      (Val, V)
 		      in  let <_cor5> =
 			      %% Line 21
-			      ~{~<1337,_cor4>,~<'val',_cor2>|M}~
+			      ~{1337:=_cor4,'val':=_cor2|M}~
 			  in  %% Line 21
 			      apply 'call'/2
 				  (_cor5, Vs)