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// P0624R2
// { dg-do compile { target c++11 } }
#if __cplusplus >= 201402L
#define A auto
#else
#define A int
#endif
void
f1 ()
{
auto greater = [](A x, A y) { return x > y; }; // { dg-message "a lambda closure type has a deleted (default constructor|copy assignment operator)" "" { target c++17_down } }
decltype (greater) gt; // { dg-error "use of deleted function" "" { target c++17_down } }
gt = greater; // { dg-error "use of deleted function" "" { target c++17_down } }
}
void
f2 ()
{
auto greater = [&](A x, A y) { return x > y; }; // { dg-message "a lambda closure type has a deleted (default constructor|copy assignment operator)" }
decltype (greater) gt; // { dg-error "use of deleted function" }
gt = greater; // { dg-error "use of deleted function" }
}
void
f3 ()
{
auto greater = [=](A x, A y) { return x > y; }; // { dg-message "a lambda closure type has a deleted (default constructor|copy assignment operator)" }
decltype (greater) gt; // { dg-error "use of deleted function" }
gt = greater; // { dg-error "use of deleted function" }
}
void
f4 (int i)
{
auto greater = [i](A x, A y) { return x > y; }; // { dg-message "a lambda closure type has a deleted (default constructor|copy assignment operator)" }
decltype (greater) gt; // { dg-error "use of deleted function" }
gt = greater; // { dg-error "use of deleted function" }
}
#if __cplusplus > 201703L
void
f5 ()
{
auto greater = [](auto x, auto y) constexpr { return x > y; };
decltype (greater) gt;
static_assert (!gt (1, 2));
static_assert (gt (4, 3));
static_assert (!gt (3.5, 3.75));
static_assert (gt (3.5, 3.25));
gt = greater;
static_assert (!gt (1, 2));
static_assert (gt (4, 3));
static_assert (!gt (3.5, 3.75));
static_assert (gt (3.5, 3.25));
}
#endif
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