std::experimental::boyer_moore_searcher,std::experimental::make_boyer_moore_searcher (3) - Linux Man Pages

std::experimental::boyer_moore_searcher,std::experimental::make_boyer_moore_searcher: std::experimental::boyer_moore_searcher,std::experimental::make_boyer_moore_searcher

NAME

std::experimental::boyer_moore_searcher,std::experimental::make_boyer_moore_searcher - std::experimental::boyer_moore_searcher,std::experimental::make_boyer_moore_searcher

Synopsis


Defined in header <experimental/functional>
template< class RandomIt1,
class Hash = std::hash<typename std::iterator_traits<RandomIt1>::value_type>, (library fundamentals TS)
class BinaryPredicate = std::equal_to<> >
class boyer_moore_searcher;


A searcher suitable for use with std::experimental::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::experimental::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, CopyConstructible and CopyAssignable.
For any two values A and B of the type std::iterator_traits<RandomIt1>::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 BinaryPredicate or Hash.


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


 std::experimental::boyer_moore_searcher::operator()


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


The member function called by std::experimental::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 examined

Return value


If the pattern ([pat_first, pat_last)) is empty, returns first. (until C++17)
Otherwise, an iterator to the first position in [first, last) where a subsequence that compares equal to [pat_first, pat_last) as defined by pred is located, or a copy of last otherwise.
If the pattern ([pat_first, pat_last)) is empty, returns make_pair(first, first). (since C++17)
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 make_pair(last, last) otherwise.


Helper Functions


template< class RandomIt,
class Hash = std::hash<typename std::iterator_traits<RandomIt>::value_type>,
class BinaryPredicate = std::equal_to<> >
boyer_moore_searcher<RandomIt, Hash, BinaryPredicate> make_boyer_moore_searcher( (library fundamentals TS)
RandomIt pat_first,
RandomIt pat_last,
Hash hf = Hash(),
BinaryPredicate pred = BinaryPredicate());


Helper function that constructs a std::experimental::boyer_moore_searcher using template argument deduction. Equivalent to return boyer_moore_searcher<RandomIt, Hash, BinaryPredicate>(pat_first, pat_last, hf, pred);

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

Return value


A boyer_moore_searcher constructed with the arguments pat_first, pat_last, hf, and pred.

Example


// Run this code


  #include <iostream>
  #include <string>
  #include <experimental/algorithm>
  #include <experimental/functional>


  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_boyer_moore_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


       searches for a range of elements
search (function template)