From d5c53554e5d71e3518a446b634428bb66fc369fd Mon Sep 17 00:00:00 2001
From: Sona Kurazyan <sona.kurazyan@qt.io>
Date: Mon, 12 Oct 2020 14:24:07 +0200
Subject: Loosen the requirements on the container passed to QtConcurrent::map*
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Using std::begin() and std::end() forces the user to have const begin()
and end() member functions being defined for the passed container. This
is because std::declval<T>() returns rvalue which forces the compiler
to select std::{begin, end}()(const Container &c) overloads and an test
for a presence of const {begin, end}() methods.

Change-Id: I9d96d9f73891ece53224f1741a1334500f7b35ad
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
---
 src/concurrent/qtconcurrentfunctionwrappers.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'src/concurrent/qtconcurrentfunctionwrappers.h')

diff --git a/src/concurrent/qtconcurrentfunctionwrappers.h b/src/concurrent/qtconcurrentfunctionwrappers.h
index bb78ea9953..be95416759 100644
--- a/src/concurrent/qtconcurrentfunctionwrappers.h
+++ b/src/concurrent/qtconcurrentfunctionwrappers.h
@@ -77,7 +77,7 @@ struct Argument
 template <class Sequence>
 struct Argument<Sequence, typename std::enable_if<IsIterableValue<Sequence>>::type>
 {
-    using Type = std::decay_t<decltype(*std::begin(std::declval<Sequence>()))>;
+    using Type = std::decay_t<decltype(*std::declval<Sequence>().begin())>;
 };
 
 template <class Iterator>
-- 
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