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Front Page / Algorithms / Querying Algorithms / find

find

Synopsis

template<
      typename Sequence
    , typename T
    >
struct find
{
    typedef unspecified type;
};

Description

Returns an iterator to the first occurrence of type T in a Sequence.

Header

#include <boost/mpl/find.hpp>

Parameters

Parameter Requirement Description
Sequence Forward Sequence A sequence to search in.
T Any type A type to search for.

Expression semantics

For any Forward Sequence s and arbitrary type t:

typedef find<s,t>::type i;
Return type:

Forward Iterator.

Semantics:

Equivalent to

typedef find_if<s, is_same<_,t> >::type i;

Complexity

Linear. At most size<s>::value comparisons for identity.

Example

typedef vector<char,int,unsigned,long,unsigned long> types;
typedef find<types,unsigned>::type iter;

BOOST_MPL_ASSERT(( is_same< deref<iter>::type, unsigned > ));
BOOST_MPL_ASSERT_RELATION( iter::pos::value, ==, 2 );

See also

Querying Algorithms, contains, find_if, count, lower_bound