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std::ranges::take_view<V>:: reserve_hint

From cppreference.net
C++
Ranges library
Range adaptors
std::ranges::take_view
constexpr auto reserve_hint ( )
(1) (since C++26)
constexpr auto reserve_hint ( ) const
(2) (since C++26)

Let W be V for overload (1) or const V for overload (2) . Equivalent to

if constexpr ( ranges :: approximately_sized_range < W > )
{
auto n = static_cast < ranges:: range_difference_t < W >> ( ranges :: reserve_hint ( base_ ) ) ;
return to-unsigned-like ( ranges:: min ( n, count_ ) ) ;
}
return to-unsigned-like ( count_ ) ;

Contents

Return value

The approximate size of the resulting range.

Notes

Feature-test macro Value Std Feature
__cpp_lib_ranges_reserve_hint 202502L (C++26) ranges::approximately_sized_range and reserve_hint (1,2)

Example

This section is incomplete
Reason: no example

See also

returns the number of elements, provided only if the underlying (adapted) range satisfies sized_range
(public member function)