table of contents
std::in_range(3) | C++ Standard Libary | std::in_range(3) |
NAME¶
std::in_range - std::in_range
Synopsis¶
Defined in header <utility>
template< class R, class T > (since C++20)
constexpr bool in_range( T t ) noexcept;
Returns true if the value of t is in the range of values that can be
represented in
R, that is, if t can be converted to R without data loss.
It is a compile-time error if either T or R is not a signed or unsigned
integer type
(including standard integer type and extended integer type).
Parameters¶
t - value to test
Return value¶
true if the value of t is representable in R, false otherwise.
Possible implementation¶
template< class R, class T >
constexpr bool in_range( T t ) noexcept
{
return std::cmp_greater_equal(t, std::numeric_limits<R>::min())
&&
std::cmp_less_equal(t, std::numeric_limits<R>::max());
}
Notes¶
This function cannot be used with enums (including std::byte),
char, char8_t,
char16_t, char32_t, wchar_t and bool.
Feature-test macro: __cpp_lib_integer_comparison_functions
Example¶
// Run this code
#include <utility>
#include <iostream>
int main()
{
std::cout << std::boolalpha;
std::cout << std::in_range<std::size_t>(-1) << '\n';
std::cout << std::in_range<std::size_t>(42) << '\n';
}
Output:¶
false
true
See also¶
ranges::min returns the smaller of the given values
(C++20) (niebloid)
ranges::max returns the greater of the given values
(C++20) (niebloid)
ranges::clamp clamps a value between a pair of boundary values
(C++20) (niebloid)
lerp linear interpolation function
(C++20) (function)
2022.07.31 | http://cppreference.com |