From 71c5b1b3548dcb3dc380d343c3b828a8df73b68d Mon Sep 17 00:00:00 2001
From: Nathan Shively-Sanders <nathansa@microsoft.com>
Date: Wed, 23 Aug 2017 15:00:12 -0700
Subject: [PATCH] Parsing:Allow QuestionToken as start of type

---
 src/compiler/parser.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index a2fe752ad18..7486c7541be 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -2721,6 +2721,7 @@ namespace ts {
                 case SyntaxKind.FalseKeyword:
                 case SyntaxKind.ObjectKeyword:
                 case SyntaxKind.AsteriskToken:
+                case SyntaxKind.QuestionToken:
                     return true;
                 case SyntaxKind.MinusToken:
                     return lookAhead(nextTokenIsNumericLiteral);