std::ranges::transform_view<V,F>::size
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< cpp | ranges | transform view
C++
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std::ranges::transform_view
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transform_view::size | ||||
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constexpr
auto size(
) requires ranges::sized_range
<V>
;
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(since C++20) | |
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constexpr
auto size(
)
const requires ranges::sized_range
<
const V>
;
|
(since C++20) | |
Returns the number of elements.
Returns ranges::size(base_), where base_
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 <cassert> #include <cctype> #include <iostream> #include <ranges> #include <string> int main() { std::string s{"The length of this string is 42 characters"}; auto to_upper = [](unsigned char c) -> char { return std::toupper(c); }; auto tv = std::ranges::transform_view{s, to_upper}; assert(tv.size() == 42); for (auto x : tv) std::cout << x; }
Output:
THE LENGTH OF THIS STRING IS 42 CHARACTERS
See also
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(C++20)
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returns an integer equal to the size of a range (customization point object) |
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(C++20)
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returns a signed integer equal to the size of a range (customization point object) |