1[/ 2 Copyright 2010 Neil Groves 3 Distributed under the Boost Software License, Version 1.0. 4 (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 5/] 6[section:count count] 7 8[heading Prototype] 9 10`` 11template<class SinglePassRange, class Value> 12typename range_difference<SinglePassRange>::type 13count(SinglePassRange& rng, const Value& val); 14 15template<class SinglePassRange, class Value> 16typename range_difference<const SinglePassRange>::type 17count(const SinglePassRange& rng, const Value& val); 18`` 19 20[heading Description] 21 22`count` returns the number of elements `x` in `rng` where `x == val` is `true`. 23 24[heading Definition] 25 26Defined in the header file `boost/range/algorithm/count.hpp` 27 28[heading Requirements] 29 30* `SinglePassRange` is a model of the __single_pass_range__ Concept. 31* `Value` is a model of the `EqualityComparableConcept`. 32* `SinglePassRange`'s value type is a model of the `EqualityComparableConcept`. 33* An object of `SinglePassRange`'s value type can be compared for equality with an object of type `Value`. 34 35[heading Complexity] 36 37Linear. Exactly `distance(rng)` comparisons. 38 39[endsect] 40 41 42