support return statement with no arguments

moonscript/compile/line.lua

@@ -130,7 +130,11 @@ line_compile = {
     })
   end,
   ["return"] = function(self, node)
-    return self:line("return ", self:value(node[2]))
+    return self:line("return ", (function()
+      if node[2] ~= "" then
+        return self:value(node[2])
+      end
+    end)())
   end,
   ["break"] = function(self, node)
     return "break"

moonscript/compile/line.moon

@@ -64,7 +64,7 @@ line_compile =
     @stm {"assign", {name}, {{"exp", name, op_final, exp}}}
 
   return: (node) =>
-    @line "return ", @value node[2]
+    @line "return ", if node[2] != "" then @value node[2]
 
   break: (node) =>
     "break"

moonscript/parse.lua

@@ -291,7 +291,7 @@ local build_grammar = wrap(function()
 
 		BreakLoop = Ct(key"break"/trim),
 
-		Return = key"return" * (ExpListLow/ mark"explist") / mark"return",
+		Return = key"return" * (ExpListLow/mark"explist" + C"") / mark"return",
 
 		With = key"with" * Exp * key"do"^-1 * Body / mark"with",
 

tests/inputs/funcs.moon

@@ -52,3 +52,10 @@ something = (hello=100, world=(x=[[yeah cool]])-> print "eat rice") ->
 (@x=1,y,@z="hello world") =>
 
 
+x -> return
+y -> return 1
+z -> return 1, "hello", "world"
+k -> if yes then return else return
+
+
+

tests/outputs/funcs.lua

@@ -93,4 +93,20 @@ _ = function(self, x, y, z)
     z = "hello world"
   end
   self.x, self.z = x, z
-end
+end
+x(function()
+  return 
+end)
+y(function()
+  return 1
+end)
+z(function()
+  return 1, "hello", "world"
+end)
+k(function()
+  if yes then
+    return 
+  else
+    return 
+  end
+end)

todo

@@ -3,20 +3,9 @@
 if hello else world
  ->  if hello then hello else world
 
-
-- enhance with documentation
-- fix variable names starting with and, not, or, etc..
-
 - varargs that get put in a nested generated function aren't valid anymore:
 
-- cascading expressions in function call? this looks too much like line decorator
-* maybe with assigns only
-
-	my_func if something
-	  "one arg"
-	else
-	  "other arg"
-
+- allow a return without an argument
 
 - class expressions, x = class extends Hello do new: => print "hello"