forked from boostorg/algorithm
83 lines
2.7 KiB
C++
83 lines
2.7 KiB
C++
|
/*
|
||
|
|
Copyright (c) Marshall Clow 2008-2012.
|
||
|
|
|
||
|
|
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
||
|
|
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
||
|
|
*/
|
||
|
|
|
||
|
|
/// \file one_of.hpp
|
||
|
|
/// \brief Test ranges to see if only one element matches a value or predicate.
|
||
|
|
/// \author Marshall Clow
|
||
|
|
|
||
|
|
#ifndef BOOST_ALGORITHM_ONE_OF_HPP
|
||
|
|
#define BOOST_ALGORITHM_ONE_OF_HPP
|
||
|
|
|
||
|
|
#include <algorithm> // for std::find and std::find_if
|
||
|
|
#include <boost/algorithm/cxx11/none_of.hpp>
|
||
|
|
|
||
|
|
#include <boost/range/begin.hpp>
|
||
|
|
#include <boost/range/end.hpp>
|
||
|
|
|
||
|
|
namespace boost { namespace algorithm {
|
||
|
|
|
||
|
|
/// \fn one_of ( InputIterator first, InputIterator last, Predicate p )
|
||
|
|
/// \return true if the predicate 'p' is true for exactly one item in [first, last).
|
||
|
|
///
|
||
|
|
/// \param first The start of the input sequence
|
||
|
|
/// \param last One past the end of the input sequence
|
||
|
|
/// \param p A predicate for testing the elements of the sequence
|
||
|
|
///
|
||
|
|
template<typename InputIterator, typename Predicate>
|
||
|
|
bool one_of ( InputIterator first, InputIterator last, Predicate p )
|
||
|
|
{
|
||
|
|
InputIterator i = std::find_if (first, last, p);
|
||
|
|
if (i == last)
|
||
|
|
return false; // Didn't occur at all
|
||
|
|
return boost::algorithm::none_of (++i, last, p);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// \fn one_of ( const Range &r, Predicate p )
|
||
|
|
/// \return true if the predicate 'p' is true for exactly one item in the range.
|
||
|
|
///
|
||
|
|
/// \param r The input range
|
||
|
|
/// \param p A predicate for testing the elements of the range
|
||
|
|
///
|
||
|
|
template<typename Range, typename Predicate>
|
||
|
|
bool one_of ( const Range &r, Predicate p )
|
||
|
|
{
|
||
|
|
return boost::algorithm::one_of ( boost::begin (r), boost::end (r), p );
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
/// \fn one_of_equal ( InputIterator first, InputIterator last, const V &val )
|
||
|
|
/// \return true if the value 'val' exists only once in [first, last).
|
||
|
|
///
|
||
|
|
/// \param first The start of the input sequence
|
||
|
|
/// \param last One past the end of the input sequence
|
||
|
|
/// \param val A value to compare against
|
||
|
|
///
|
||
|
|
template<typename InputIterator, typename V>
|
||
|
|
bool one_of_equal ( InputIterator first, InputIterator last, const V &val )
|
||
|
|
{
|
||
|
|
InputIterator i = std::find (first, last, val); // find first occurrence of 'val'
|
||
|
|
if (i == last)
|
||
|
|
return false; // Didn't occur at all
|
||
|
|
return boost::algorithm::none_of_equal (++i, last, val);
|
||
|
|
}
|
||
|
|
|
||
|
|
/// \fn one_of_equal ( const Range &r, const V &val )
|
||
|
|
/// \return true if the value 'val' exists only once in the range.
|
||
|
|
///
|
||
|
|
/// \param r The input range
|
||
|
|
/// \param val A value to compare against
|
||
|
|
///
|
||
|
|
template<typename Range, typename V>
|
||
|
|
bool one_of_equal ( const Range &r, const V &val )
|
||
|
|
{
|
||
|
|
return boost::algorithm::one_of_equal ( boost::begin (r), boost::end (r), val );
|
||
|
|
}
|
||
|
|
|
||
|
|
}} // namespace boost and algorithm
|
||
|
|
|
||
|
|
#endif // BOOST_ALGORITHM_ALL_HPP
|