std::ranges::concat_view<Views...>::begin
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< cpp | ranges | concat view
C++
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constexpr
/*iterator*/
<
false
> begin(
)
requires ( ! ( /*simple-view*/ <Views> && ...) ) ; |
(1) | (since C++26) |
|
constexpr
/*iterator*/
<
true
> begin(
)
const
requires (
ranges::range
<
const Views>
&& ...)
&&
|
(2) | (since C++26) |
Returns an iterator to the beginning of the concat_view.
1) Equivalent to
it.template
return it;
iterator
<
false
> it(this, std::in_place_index
<
0
>
views_ )));
it.template
satisfy <0>();
return it;
2) Equivalent to
it.template
return it;
iterator
<
true
> it(this, std::in_place_index
<
0
>
views_ )));
it.template
satisfy <0>();
return it;
Return value
As specified above.
Example
The preliminary version can be checked out on Compiler Explorer.
Run this code
#include <ranges> #include <string_view> using namespace std::literals; int main() { static constexpr auto c = {"🐱", "🐶"}; static constexpr auto a = {"🤡"sv}; static constexpr auto t = {"💚"sv}; static constexpr auto cat{std::views::concat(c, a, t)}; static_assert(*cat.begin() == "\U0001F431" and cat.begin()[1] == "🐶" and *(cat.begin() + 2) == "\N{CLOWN FACE}"); }
See also
| returns an iterator or a sentinel to the end (public member function) |
|
|
(C++20)
|
returns an iterator to the beginning of a range (customization point object) |