fixed being unable to use 'yield throw'

lib/coffee-script/nodes.js

@@ -2530,7 +2530,7 @@
       if (o.scope.parent == null) {
         this.error('yield statements must occur within a function generator.');
       }
-      if (indexOf.call(Object.keys(this.first), 'expression') >= 0) {
+      if (indexOf.call(Object.keys(this.first), 'expression') >= 0 && !(this.first instanceof Throw)) {
         if (this.first.expression != null) {
           parts.push(this.first.expression.compileToFragments(o, LEVEL_OP));
         }

src/nodes.coffee

@@ -1801,7 +1801,7 @@ exports.Op = class Op extends Base
     op = @operator
     if not o.scope.parent?
       @error 'yield statements must occur within a function generator.'
-    if 'expression' in Object.keys @first
+    if 'expression' in Object.keys(@first) and not (@first instanceof Throw)
       parts.push @first.expression.compileToFragments o, LEVEL_OP if @first.expression?
     else
       parts.push [@makeCode "(#{op} "]

test/generators.coffee

@@ -124,3 +124,14 @@ test "switch expressions", ->
   ok z.value is 1337 and z.done is false
   z = x.next 3
   ok z.value is 3 and z.done is true
+
+test "`yield` can be thrown", ->
+  x = do ->
+    throw yield null
+  x.next()
+  throws -> x.next new Error "boom"
+
+test "`throw` can be yielded", ->
+  x = do ->
+    yield throw new Error "boom"
+  throws -> x.next()