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std::boyer_moore_searcher(3)  C++ Standard Libary std::boyer_moore_searcher(3)

NAME
       std::boyer_moore_searcher - std::boyer_moore_searcher

Synopsis
	  Defined in header <functional>
	  template< class RandomIt1,

	  class	Hash = std::hash<typename
	  std::iterator_traits<RandomIt1>::value_type>,
       (since C++17)
	  class	BinaryPredicate	= std::equal_to<> >

	  class	boyer_moore_searcher;

	  A   searcher	 suitable  for	use  with  the	Searcher  overload  of
       std::search that
	  implements the Boyer-Moore string searching algorithm.

	  boyer_moore_searcher is CopyConstructible and	CopyAssignable.

	  RandomIt1 must meet the requirements of LegacyRandomAccessIterator.

Member functions
       std::boyer_moore_searcher::boyer_moore_searcher

	  boyer_moore_searcher(	RandomIt1 pat_first,

	  RandomIt1 pat_last,
	  Hash hf = Hash(),

	  BinaryPredicate pred = BinaryPredicate());

	  Constructs a boyer_moore_searcher by storing	copies	of  pat_first,
       pat_last, hf, and
	  pred,	setting	up any necessary internal data structures.

	  The  value  type of RandomIt1	must be	DefaultConstructible, CopyCon-
       structible and
	  CopyAssignable.

	  For any two values A and B  of  the  type  std::iterator_traits<Ran-
       domIt1>::value_type,
	  if pred(A, B)	== true, then hf(A) == hf(B) shall be true.

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

Exceptions
	  Any exceptions thrown	by

	    * the copy constructor of RandomIt1;
	    * the default constructor, copy constructor, and  copy  assignment
       operator	of the
	      value type of RandomIt1; or
	    *  the copy	constructor and	function call operator of BinaryPredi-
       cate or Hash.

	  May also throw std::bad_alloc	if additional memory required for  in-
       ternal data
	  structures cannot be allocated.

       std::boyer_moore_searcher::operator()

	  template< class RandomIt2 >
	  std::pair<RandomIt2,RandomIt2>  operator()(  RandomIt2  first,  Ran-
       domIt2  (since C++17)
	  last ) const;

	  The member function called by	the Searcher overload  of  std::search
       to perform a
	  search with this searcher. RandomIt2 must meet the requirements of
	  LegacyRandomAccessIterator.

	  RandomIt1 and	RandomIt2 must have the	same value type.

Parameters
	  first, last -	a pair of iterators designating	the string to be exam-
       ined

Return value
	  If   the   pattern   ([pat_first,   pat_last))   is  empty,  returns
       std::make_pair(first,
	  first).

	  Otherwise, returns 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 std::make_pair(last, last) otherwise.

Notes
	  Feature-test macro: __cpp_lib_boyer_moore_searcher

Example
       // Run this code

	#include <iomanip>
	#include <iostream>
	#include <algorithm>
	#include <functional>
	#include <string_view>

	int main()
	{
	    constexpr std::string_view haystack	=
		"Lorem	ipsum dolor sit	amet, consectetur adipiscing elit, sed
       "
		"do eiusmod tempor incididunt ut labore	et dolore  magna  ali-
       qua";

	    const std::string_view needle {"pisci"};

	    if (const auto it =	std::search(haystack.begin(), haystack.end(),
		    std::boyer_moore_searcher(needle.begin(), needle.end()));
		it != haystack.end()
	    ) {
		std::cout  <<  "The  string  " << quoted(needle) << " found at
       offset "
			  << it	- haystack.begin() << '\n';
	    } else {
		std::cout << "The string " <<  std::quoted(needle)  <<	"  not
       found\n";
	    }
	}

Output:
	The string "pisci" found at offset 43

See also
	  search			searches for a range of	elements
					(function template)
	  default_searcher		 standard C++ library search algorithm
       implementation
	  (C++17)			(class template)
	  boyer_moore_horspool_searcher	Boyer-Moore-Horspool search  algorithm
       implementation
	  (C++17)			(class template)

http://cppreference.com		  2022.07.31	  std::boyer_moore_searcher(3)

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