std::experimental::default_searcher,std::experimental::make_default_searcher

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Experimental

Technical Specification
Filesystem library(filesystem TS)
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Library fundamentals

experimental::optional
experimental::any
experimental::basic_string_view
experimental::sample
experimental::shared_ptr
experimental::weak_ptr
experimental::apply
experimental::invocation_typeexperimental::raw_invocation_type
experimental::search
experimental::default_searcherexperimental::make_default_searcher
experimental::boyer_moore_searcherexperimental::make_boyer_moore_searcher
experimental::boyer_moore_horspool_searcherexperimental::make_boyer_moore_horspool_searcher
Type-erased and polymorphic allocators
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Defined in header`<experimental/functional>`
template<class ForwardIterator1,class BinaryPredicate=std::equal_to<>> class default_searcher;		(library fundamentals TS)

A class suitable for use withstd::experimental::search that delegates the search operation to the standard library'sstd::search.

default_searcher isCopyConstructible andCopyAssignable.

[edit]Member functions

std::experimental::default_searcher::default_searcher

default_searcher( ForwardIterator pat_first, ForwardIterator pat_last, BinaryPredicate pred= BinaryPredicate());

Constructs adefault_searcher by storing copies ofpat_first,pat_last, andpred.

Parameters

pat_first, pat_last	-	a pair of iterators designating the string to be searched for
pred	-	a callable object used to determine equality

Exceptions

Any exceptions thrown by the copy constructors ofBinaryPredicate orForwardIterator.

std::experimental::default_searcher::operator()

template<class ForwardIterator2> ForwardIterator2 operator()( ForwardIterator2 first, ForwardIterator2 last)const;		(until C++17)
template<class ForwardIterator2> std::pair<ForwardIterator2, ForwardIterator2> operator()( ForwardIterator2 first, ForwardIterator2 last)const;		(since C++17)

The member function called bystd::experimental::search to perform a search with this searcher.

Equivalent tostd::search(first, last, pat_first, pat_last, pred);.	(until C++17)
Returns a pair of iterators`i, j`, where`i` isstd::search(first, last, pat_first, pat_last, pred) and`j` isstd::next(i,std::distance(pat_first, pat_last)) unless`std::search` returnedlast (no match), in which case`j` equalslast as well.	(until C++17)

Parameters

first, last

a pair of iterators designating the string to be examined

Return value

Iterator to the first position in`[`first`,` last`)` where a subsequence that compares equal to`[`pat_first`,` pat_last`)` as defined bypred is located, or a copy oflast otherwise.	(until C++17)
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 bypred is located, or a pair of copies oflast otherwise.	(since C++17)

[edit]Helper Functions

template<class ForwardIterator,class BinaryPredicate=std::equal_to<>> default_searcher<ForwardIterator, BinaryPredicate> make_default_searcher( ForwardIterator pat_first, ForwardIterator pat_last, BinaryPredicate pred= BinaryPredicate());		(library fundamentals TS)

Helper function that constructs astd::experimental::default_searcher using template argument deduction. Equivalent toreturn default_searcher<ForwardIterator, BinaryPredicate>(pat_first, pat_last, pred);

[edit]Parameters

pat_first, pat_last	-	a pair of iterators designating the string to be searched for
pred	-	a callable object used to determine equality

[edit]Return value

Adefault_searcher constructed with the argumentspat_first,pat_last,pred.

[edit]Example

Run this code

#include <experimental/algorithm>#include <experimental/functional>#include <iostream>#include <string> int main(){std::string in="Lorem ipsum dolor sit amet, consectetur adipiscing elit,"" sed do eiusmod tempor incididunt ut labore et dolore magna aliqua";std::string needle="pisci";auto it=std::experimental::search(in.begin(), in.end(),                  std::experimental::make_default_searcher(                      needle.begin(), needle.end()));if(it!= in.end())std::cout<<"The string "<< needle<<" found at offset "<< it- in.begin()<<'\n';elsestd::cout<<"The string "<< needle<<" not found\n";}