From 7f413ec31d3c7ad9cde6f5fe4ec06d9ee6b758b2 Mon Sep 17 00:00:00 2001
From: James Sedgwick <jsedgwick@fb.com>
Date: Thu, 30 Apr 2015 13:13:55 -0700
Subject: [PATCH] fix return type for map

Summary:
facepalm

Test Plan: unit

Reviewed By: hans@fb.com

Subscribers: folly-diffs@, jsedgwick, yfeldblum, chalfant

FB internal diff: D2036523

Tasks: 6925951

Signature: t1:2036523:1430423049:b69ace0256eeacdd43490465dc1c862f054a0098
---
 folly/futures/helpers.h           | 3 ++-
 folly/futures/test/FutureTest.cpp | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/folly/futures/helpers.h b/folly/futures/helpers.h
index 7fd79508..c39d6686 100644
--- a/folly/futures/helpers.h
+++ b/folly/futures/helpers.h
@@ -58,7 +58,8 @@ namespace futures {
    */
   template <class It, class F,
             class ItT = typename std::iterator_traits<It>::value_type,
-            class Result = decltype(std::declval<ItT>().then(std::declval<F>()))>
+            class Result
+      = typename decltype(std::declval<ItT>().then(std::declval<F>()))::value_type>
   std::vector<Future<Result>> map(It first, It last, F func);
 
   // Sugar for the most common case
diff --git a/folly/futures/test/FutureTest.cpp b/folly/futures/test/FutureTest.cpp
index da3e1c5c..5b7be306 100644
--- a/folly/futures/test/FutureTest.cpp
+++ b/folly/futures/test/FutureTest.cpp
@@ -1765,7 +1765,7 @@ TEST(Map, Basic) {
   fs.push_back(p3.getFuture());
 
   int c = 0;
-  auto fs2 = futures::map(fs, [&](int i){
+  std::vector<Future<void>> fs2 = futures::map(fs, [&](int i){
     c += i;
   });
 
-- 
2.34.1