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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// utilities
// exchange
#include <utility>
#include <cassert>
#include <string>
int main()
{
#if _LIBCPP_STD_VER > 11
{
int v = 12;
assert ( std::exchange ( v, 23 ) == 12 );
assert ( v == 23 );
assert ( std::exchange ( v, 67.2 ) == 23 );
assert ( v == 67 );
assert ((std::exchange<int, float> ( v, {} )) == 67 );
assert ( v == 0 );
}
{
bool b = false;
assert ( !std::exchange ( b, true ));
assert ( b );
}
{
const std::string s1 ( "Hi Mom!" );
const std::string s2 ( "Yo Dad!" );
std::string s3 = s1; // Mom
assert ( std::exchange ( s3, s2 ) == s1 );
assert ( s3 == s2 );
assert ( std::exchange ( s3, "Hi Mom!" ) == s2 );
assert ( s3 == s1 );
s3 = s2; // Dad
assert ( std::exchange ( s3, {} ) == s2 );
assert ( s3.size () == 0 );
s3 = s2; // Dad
assert ( std::exchange ( s3, "" ) == s2 );
assert ( s3.size () == 0 );
}
#endif
}
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