Closes #1082. Puts back use of function calls in parameter lists.

lib/lexer.js

@@ -436,9 +436,10 @@
             stack.push(tok);
             break;
           case '(':
+          case 'CALL_START':
             if (stack.length) {
               stack.pop();
-            } else {
+            } else if (tok[0] === '(') {
               tok[0] = 'PARAM_START';
               return this;
             }

src/lexer.coffee

@@ -369,9 +369,9 @@ exports.Lexer = class Lexer
       switch tok[0]
         when ')'
           stack.push tok
-        when '('
+        when '(', 'CALL_START'
           if stack.length then stack.pop()
-          else
+          else if tok[0] is '('
             tok[0] = 'PARAM_START'
             return this
     this

test/function_literals.coffee

@@ -148,6 +148,9 @@ test "default values with splatted arguments", ->
   eq  1, withSplats(1,1,1)
   eq  2, withSplats(1,1,1,1)
 
+test "default values with function calls", ->
+  doesNotThrow -> CoffeeScript.compile "(x = f()) ->"
+
 test "arguments vs parameters", ->
   doesNotThrow -> CoffeeScript.compile "f(x) ->"
   f = (g) -> g()