NAME¶

std::ranges::slide_view::begin - std::ranges::slide_view::begin

Synopsis¶

constexpr auto begin()
requires (!(__simple_view<V> && __slide_caches_nothing<const (1) (since C++23)
V>));
constexpr auto begin() const (2) (since C++23)
requires __slide_caches_nothing<const V>;

Returns an iterator to the first element of the slide_view.

1) If V models __slide_caches_first, equivalent to:

return iterator<false>(
ranges::begin(base_),
ranges::next(ranges::begin(base_), n_ - 1, ranges::end(base_)),
n_
);

Otherwise, equivalent to: return iterator<false>(ranges::begin(base_), n_);.
If V models __slide_caches_first this function caches the result within the
slide_view::cached_begin_ for use on subsequent calls. This is necessary to provide
the amortized constant-time complexity required by the range.
2) Equivalent to: return iterator<true>(ranges::begin(base_), n_);.

Parameters¶

(none)

Return value¶

An iterator to the first element of slide_view, which points to the n_-sized
subrange of the possibly const-qualified underlying view type – V for overload (1)
or const V for overload (2).

Example¶

// Run this code

#include <iostream>
#include <ranges>
#include <string_view>
using namespace std::literals;

int main()
{
static constexpr auto source = {"∀x"sv, "∃y"sv, "ε"sv, "δ"sv};
auto view{std::ranges::slide_view(source, 2)};
const auto subrange{*(view.begin())};
for (std::string_view const s : subrange)
std::cout << s << ' ';
std::cout << '\n';
}

Output:¶

∀x ∃y

See also¶

end returns an iterator or a sentinel to the end
(C++23) (public member function)
operator== compares a sentinel with an iterator returned from slide_view::begin
(C++23) (function)