From 69f2a0d3f1fd72625e2e7d630360f2d5e19e688d Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Wed, 28 Jan 2015 20:01:55 +1100
Subject: [PATCH] better t.toIdentifier behaviour that doesn't camelcase on
 underscores - fixes #610

---
 lib/6to5/types/index.js | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/lib/6to5/types/index.js b/lib/6to5/types/index.js
index a1e1135290..8d56f4aa2d 100644
--- a/lib/6to5/types/index.js
+++ b/lib/6to5/types/index.js
@@ -226,7 +226,7 @@ t.prependToMemberExpression = function (member, append) {
 };
 
 /**
- * Description
+ * Check if the input `node` is going to be evaluated, ie. is a refernece.
  *
  * @param {Object} node
  * @param {Object} parent
@@ -331,13 +331,10 @@ t.toIdentifier = function (name) {
   name = name.replace(/^[-0-9]+/, "");
 
   // camel case
-  name = name.replace(/[-_\s]+(.)?/g, function (match, c) {
+  name = name.replace(/[-\s]+(.)?/g, function (match, c) {
     return c ? c.toUpperCase() : "";
   });
 
-  // remove underscores from start of name
-  name = name.replace(/^\_/, "");
-
   if (!t.isValidIdentifier(name)) {
     name = "_" + name;
   }