From 6128fd968701cec78acf6b12215db4e64a3ed90d Mon Sep 17 00:00:00 2001
From: Sebastian McKenzie <sebmck@gmail.com>
Date: Sun, 22 Mar 2015 04:06:15 +1100
Subject: [PATCH] add do expressions

---
 src/expression.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/expression.js b/src/expression.js
index b40024559f..0702837dcb 100755
--- a/src/expression.js
+++ b/src/expression.js
@@ -245,6 +245,14 @@ pp.parseExprAtom = function(refShorthandDefaultPos) {
   case tt._yield:
     if (this.inGenerator) unexpected()
 
+  case tt._do:
+    if (this.options.features["es7.doExpressions"]) {
+      let node = this.startNode()
+      this.next()
+      node.body = this.parseBlock()
+      return this.finishNode(node, "DoExpression")
+    }
+
   case tt.name:
     let start = this.markPosition()
     node = this.startNode()