Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
std::boyer_...ol_searcher(3)  C++ Standard Libary std::boyer_...ol_searcher(3)

NAME
       std::boyer_moore_horspool_searcher - std::boyer_moore_horspool_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_horspool_searcher;

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

	  boyer_moore_horspool_searcher	is CopyConstructible and  CopyAssigna-
       ble.

	  RandomIt1 must meet the requirements of LegacyRandomAccessIterator.

Member functions
       std::boyer_moore_horspool_searcher::boyer_moore_horspool_searcher

	  boyer_moore_horspool_searcher( RandomIt1 pat_first,

	  RandomIt1 pat_last,
	  Hash hf = Hash(),

	  BinaryPredicate pred = BinaryPredicate());

	  Constructs  a	 boyer_moore_horspool_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, or copy assignment
       operator	of the
	      value type of RandomIt1; or
	    * the copy constructor or 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_horspool_searcher::operator()

	  template< class RandomIt2 >
	  std::pair<RandomIt2,RandomIt2>  operator()(  RandomIt2  first,  Ran-
       domIt2 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 <iostream>
	#include <string>
	#include <algorithm>
	#include <functional>

	int main()
	{
	    std::string	in = "Lorem ipsum dolor	sit amet, consectetur adipisc-
       ing elit,"
			     " sed do eiusmod tempor incididunt	ut  labore  et
       dolore magna aliqua";
	    std::string	needle = "pisci";
	    auto it = std::search(in.begin(), in.end(),
			   std::boyer_moore_horspool_searcher(
			       needle.begin(), needle.end()));
	    if(it != in.end())
		std::cout << "The string " << needle <<	" found	at offset "
			  << it	- in.begin() <<	'\n';
	    else
		std::cout << "The string " << 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 implemen-
       tation
	  (C++17)	       (class template)
	  boyer_moore_searcher Boyer-Moore search algorithm implementation
	  (C++17)	       (class template)

http://cppreference.com		  2022.07.31	  std::boyer_...ol_searcher(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::boyer_moore_horspool_searcher&sektion=3&manpath=FreeBSD+Ports+15.0>

home | help