allowed {-true} etc.

Author: satyr

lib/grammar.js

@@ -199,7 +199,9 @@ bnf = {
     }), o('KeyValue'), o('KeyValue LOGIC Expression', function(){
       return Binary($2, $1, $3);
     }), o('+- Key', function(){
-      return Prop($2.maybeKey(), Literal($1 === '+'));
+      return Prop($2.maybeKey(), L(Literal($1 === '+')));
+    }), o('+- LITERAL', function(){
+      return Prop(L(Key($2, true)), L(Literal($1 === '+')));
     }), o('... Expression', function(){
       return Splat($2);
     }), o('COMMENT', function(){

lib/parser.js

@@ -231,7 +231,8 @@ bnf =
     o \KeyValue
     o 'KeyValue LOGIC Expression' -> Binary $2, $1, $3
 
-    o '+- Key' -> Prop $2.maybeKey(), Literal $1 is \+
+    o '+- Key'     -> Prop $2.maybeKey!   , L Literal $1 is \+
+    o '+- LITERAL' -> Prop L(Key $2, true), L Literal $1 is \+
 
     o '... Expression' -> Splat $2
 

src/grammar.co

@@ -152,26 +152,28 @@ eq obj.class + obj.function, 'hotdog'
 
 
 # Property shorthands.
-class extends Object
-  a = 0; @b = 1; x = {a, @b, 2, \3}
+new
+  a = 0; @b = 1; x = {a, @b, 2, \3, +4, -5}
   eq x.a, 0
   eq x.b, 1
   eq x.2, 2
   eq x.3, \3
+  eq x.4, true
+  eq x.5, false
   c = null; d = 0; y = {a || 1, @b && 2, c ? 3, d !? 4}
   eq y.a, 1
   eq y.b, 2
   eq y.c, 3
   eq y.d, 4
-  z = {true, false, null, void, this, arguments, eval, super}
+  z = {true, false, null, void, this, arguments, +eval, -super}
   eq z.true      , true
   eq z.false     , false
   eq z.null      , null
   eq z.void      , void
   eq z.this      , this
   eq z.arguments , arguments
-  eq z.eval      , eval
-  eq z.super     , super
+  eq z.eval      , true
+  eq z.super     , false
 
 
 # [coffee#542](https://github.com/jashkenas/coffee-script/issues/542):