diff --git a/moonscript/parse.lua b/moonscript/parse.lua
index f3fda48..da6731e 100644
--- a/moonscript/parse.lua
+++ b/moonscript/parse.lua
@@ -188,7 +188,7 @@ local build_grammar = wrap_env(debug_grammar, function(root)
     KeyValueList = KeyValue * (sym(",") * KeyValue) ^ 0,
     KeyValueLine = CheckIndent * KeyValueList * sym(",") ^ -1,
     FnArgsDef = sym("(") * White * Ct(FnArgDefList ^ -1) * (key("using") * Ct(NameList + Space * "nil") + Ct("")) * White * sym(")") + Ct("") * Ct(""),
-    FnArgDefList = FnArgDef * (sym(",") * White * FnArgDef) ^ 0 * (sym(",") * White * Ct(VarArg)) ^ 0 + Ct(VarArg),
+    FnArgDefList = FnArgDef * ((sym(",") + Break) * White * FnArgDef) ^ 0 * ((sym(",") + Break) * White * Ct(VarArg)) ^ 0 + Ct(VarArg),
     FnArgDef = Ct((Name + SelfName) * (sym("=") * Exp) ^ -1),
     FunLit = FnArgsDef * (sym("->") * Cc("slim") + sym("=>") * Cc("fat")) * (Body + Ct("")) / mark("fndef"),
     NameList = Name * (sym(",") * Name) ^ 0,
diff --git a/moonscript/parse.moon b/moonscript/parse.moon
index d1a5fff..7fd5de6 100644
--- a/moonscript/parse.moon
+++ b/moonscript/parse.moon
@@ -296,7 +296,7 @@ build_grammar = wrap_env debug_grammar, (root) ->
       (key"using" * Ct(NameList + Space * "nil") + Ct"") *
       White * sym")" + Ct"" * Ct""
 
-    FnArgDefList: FnArgDef * (sym"," * White * FnArgDef)^0 * (sym"," * White * Ct(VarArg))^0 + Ct(VarArg)
+    FnArgDefList: FnArgDef * ((sym"," + Break) * White * FnArgDef)^0 * ((sym"," + Break) * White * Ct(VarArg))^0 + Ct(VarArg)
     FnArgDef: Ct((Name + SelfName) * (sym"=" * Exp)^-1)
 
     FunLit: FnArgsDef *
diff --git a/spec/inputs/funcs.moon b/spec/inputs/funcs.moon
index 37387f8..08a29b6 100644
--- a/spec/inputs/funcs.moon
+++ b/spec/inputs/funcs.moon
@@ -129,6 +129,28 @@ y = (a="hi",
 ) ->
     print "what"
 
+--
+
+args = (a
+  b) ->
+    print "what"
+
+
+args = (a="hi"
+  b=23) ->
+    print "what"
+
+args = (
+  a="hi"
+  b=23) ->
+    print "what"
+
+
+args = (f,g,m
+  a="hi"
+  b=23
+) ->
+    print "what"
 
 
 
diff --git a/spec/outputs/funcs.lua b/spec/outputs/funcs.lua
index 43cb934..f5e2cf3 100644
--- a/spec/outputs/funcs.lua
+++ b/spec/outputs/funcs.lua
@@ -176,4 +176,35 @@ y = function(a, b, ...)
   end
   return print("what")
 end
+local args
+args = function(a, b)
+  return print("what")
+end
+args = function(a, b)
+  if a == nil then
+    a = "hi"
+  end
+  if b == nil then
+    b = 23
+  end
+  return print("what")
+end
+args = function(a, b)
+  if a == nil then
+    a = "hi"
+  end
+  if b == nil then
+    b = 23
+  end
+  return print("what")
+end
+args = function(f, g, m, a, b)
+  if a == nil then
+    a = "hi"
+  end
+  if b == nil then
+    b = 23
+  end
+  return print("what")
+end
 return nil
\ No newline at end of file