Defined in header <functional> | ||
---|---|---|
template< class ForwardIt, class BinaryPredicate = std::equal_to<> > class default_searcher; | (since C++17) |
A class suitable for use with Searcher overload of std::search
that delegates the search operation to the pre-C++17 standard library's std::search
.
std::default_searcher
is CopyConstructible and CopyAssignable.
default_searcher( ForwardIt pat_first, ForwardIt pat_last, BinaryPredicate pred = BinaryPredicate() ); | (since C++17) (until C++20) | |
constexpr default_searcher( ForwardIt pat_first, ForwardIt pat_last, BinaryPredicate pred = BinaryPredicate() ); | (since C++20) |
Constructs a std::default_searcher
by storing copies of pat_first
, pat_last
, and pred
.
pat_first, pat_last | - | a pair of iterators designating the string to be searched for |
pred | - | a callable object used to determine equality |
Any exceptions thrown by the copy constructors of BinaryPredicate
or ForwardIt
.
template< class ForwardIt2 > std::pair<ForwardIt2, ForwardIt2> operator()( ForwardIt2 first, ForwardIt2 last ) const; | (since C++17) (until C++20) | |
template< class ForwardIt2 > constexpr std::pair<ForwardIt2, ForwardIt2> operator()( ForwardIt2 first, ForwardIt2 last ) const; | (since C++20) |
The member function called by the Searcher overload of std::search
to perform a search with this searcher.
Returns a pair of iterators i, j
, where i
is std::search(first, last, pat_first, pat_last, pred)
and j
is std::next(i, std::distance(pat_first, pat_last))
unless std::search
returned last
(no match), in which case j
equals last
as well.
first, last | - | a pair of iterators designating the string to be examined |
A pair of iterators to the first and one past last positions in [
first
,
last
)
where a subsequence that compares equal to [
pat_first
,
pat_last
)
as defined by pred
is located, or a pair of copies of last
otherwise.
#include <algorithm> #include <functional> #include <iomanip> #include <iostream> #include <string_view> int main() { constexpr std::string_view in = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed " "do eiusmod tempor incididunt ut labore et dolore magna aliqua"; const std::string_view needle{"pisci"}; auto it = std::search(in.begin(), in.end(), std::default_searcher( needle.begin(), needle.end())); if (it != in.end()) std::cout << "The string " << std::quoted(needle) << " found at offset " << it - in.begin() << '\n'; else std::cout << "The string " << std::quoted(needle) << " not found\n"; }
Output:
The string "pisci" found at offset 43
searches for a range of elements (function template) |
|
(C++17) | Boyer-Moore search algorithm implementation (class template) |
(C++17) | Boyer-Moore-Horspool search algorithm implementation (class template) |
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