explicit instantiation of common Future types

[folly.git] / folly / futures / helpers.h

diff --git a/folly/futures/helpers.h b/folly/futures/helpers.h
index 7fd7950851b2b4eb32828255d246bb5cef15e8f9..744a01aca40b6110cf8172bd54d10ae35b8ed052 100644 (file)
--- 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
@@ -130,8 +131,7 @@ Future<T> makeFuture(Try<T>&& t);
  *
  * @returns a void Future that will call back on the given executor
  */
-template <typename Executor>
-Future<void> via(Executor* executor);
+inline Future<void> via(Executor* executor);
 
 /** When all the input Futures complete, the returned Future will complete.
   Errors do not cause early termination; this Future will always succeed
@@ -234,22 +234,14 @@ using isFutureResult = isFuture<typename std::result_of<F(T&&, Arg&&)>::type>;
 
     Func can either return a T, or a Future<T>
   */
-template <class It, class T, class F,
-          class ItT = typename std::iterator_traits<It>::value_type::value_type,
-          class Arg = MaybeTryArg<F, T, ItT>>
-typename std::enable_if<!isFutureResult<F, T, Arg>::value, Future<T>>::type
-reduce(It first, It last, T initial, F func);
-
-template <class It, class T, class F,
-          class ItT = typename std::iterator_traits<It>::value_type::value_type,
-          class Arg = MaybeTryArg<F, T, ItT>>
-typename std::enable_if<isFutureResult<F, T, Arg>::value, Future<T>>::type
-reduce(It first, It last, T initial, F func);
+template <class It, class T, class F>
+Future<T> reduce(It first, It last, T&& initial, F&& func);
 
 /// Sugar for the most common case
 template <class Collection, class T, class F>
 auto reduce(Collection&& c, T&& initial, F&& func)
-    -> decltype(reduce(c.begin(), c.end(), initial, func)) {
+    -> decltype(reduce(c.begin(), c.end(), std::forward<T>(initial),
+                std::forward<F>(func))) {
   return reduce(
       c.begin(),
       c.end(),