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std::ranges::transform_view::size(3) | C++ Standard Libary | std::ranges::transform_view::size(3) |
NAME¶
std::ranges::transform_view::size - std::ranges::transform_view::size
Synopsis¶
constexpr auto size() requires ranges::sized_range<V>;
(since C++20)
constexpr auto size() const requires ranges::sized_range<const V>;
(since C++20)
Returns the number of elements.
Returns ranges::size(base_), where base_ is the underlying view.
Parameters¶
(none)
Return value¶
The number of elements.
Notes¶
If V does not model forward_range, size() might not be
well-defined after a call to
begin().
Example¶
// Run this code
#include <iostream>
#include <ranges>
#include <string>
#include <cctype>
int main()
{
std::string s{"The length of this string is 42 characters"};
auto tv = std::ranges::transform_view{s, [](char c) -> char {
return std::toupper(c); }
};
for (auto x: tv) { std::cout << x; };
std::cout << "\nsize = " << tv.size() << '\n';
}
Output:¶
THE LENGTH OF THIS STRING IS 42 CHARACTERS
size = 42
See also¶
ranges::size returns an integer equal to the size of a range
(C++20) (customization point object)
ranges::ssize returns a signed integer equal to the size of a range
(C++20) (customization point object)
2022.07.31 | http://cppreference.com |