From d26afd7273c8aabfb92157df55eadbc907c6fb65 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Sun, 15 Sep 2019 11:07:51 -0700
Subject: [PATCH] for-in or for-of expression is evaluated before loop back
 edge

---
 src/compiler/binder.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/binder.ts b/src/compiler/binder.ts
index 6efc4ae05b0..5006e841dc7 100644
--- a/src/compiler/binder.ts
+++ b/src/compiler/binder.ts
@@ -1032,12 +1032,12 @@ namespace ts {
         function bindForInOrForOfStatement(node: ForInOrOfStatement): void {
             const preLoopLabel = createLoopLabel();
             const postLoopLabel = createBranchLabel();
+            bind(node.expression);
             addAntecedent(preLoopLabel, currentFlow);
             currentFlow = preLoopLabel;
             if (node.kind === SyntaxKind.ForOfStatement) {
                 bind(node.awaitModifier);
             }
-            bind(node.expression);
             addAntecedent(postLoopLabel, currentFlow);
             bind(node.initializer);
             if (node.initializer.kind !== SyntaxKind.VariableDeclarationList) {