Difference between revisions of "cpp/ranges/split view"

Revision as of 13:29, 31 October 2021

split_view models the concepts forward_range, and common_range when the underlying view V models respective concepts.

The inner range (ranges::range_reference_t<split_view>) is a ranges::subrange<ranges::iterator_t<V>>, which models common_range, models sized_range when ranges::iterator_t<V> models std::sized_sentinel_for<ranges::iterator_t<V>>, and models contiguous_range, random_access_range, bidirectional_range, and forward_range when V models respective concepts.

Expression-equivalent

Expression e is expression-equivalent to expression f, if

• e and f have the same effects, and
• either both are constant subexpressions or else neither is a constant subexpression, and
• either both are potentially-throwing or else neither is potentially-throwing (i.e. noexcept(e) == noexcept(f)).

Data members

Typical implementations of split_view hold three non-static data members:

• the underlying view of type V (shown here as base_ for exposition only), and
• the pattern (shown here as pattern_ for exposition only) that is used as a delimiter to split the underlying view.
• an object equivalent to std::optional<ranges::subrange<ranges::iterator_t<V>>> (shown here as cached_begin_ for exposition only) that caches the result of a first call to begin().

Member functions

Nested classes

Deduction guides

Notes

Example

#include <iostream>
#include <iomanip>
#include <ranges>
#include <string_view>
 
int main() {
    constexpr std::string_view words{"Hello-_-C++-_-23-_-!"};
    constexpr std::string_view delim{"-_-"};
    for (const std::string_view word : std::views::split(words, delim)) {
        std::cout << std::quoted(word) << ' ';
    }
}

"Hello" "C++" "23" "!"

See also