std::ranges::transform_view<V,F>::size
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
#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
|
(C++20)
|
returns an integer equal to the size of a range (customization point object) |
|
(C++20)
|
returns a signed integer equal to the size of a range (customization point object) |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
https://en.cppreference.com/w/cpp/ranges/transform_view/size
