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Front Page / Metafunctions / Arithmetic Operations / modulus

modulus

Synopsis

template<
      typename T1
    , typename T2
    >
struct modulus
{
    typedef unspecified type;
};

Description

Returns the modulus of its arguments.

Header

#include <boost/mpl/modulus.hpp>
#include <boost/mpl/arithmetic.hpp>

Model of

Numeric Metafunction

Parameters

Parameter Requirement Description
T1, T2 Integral Constant Operation's arguments.

[Note: The requirements listed in this specification are the ones imposed by the default implementation. See Numeric Metafunction concept for the details on how to provide an implementation for a user-defined numeric type that does not satisfy the Integral Constant requirements. — end note]

Expression semantics

For any Integral Constants c1 and c2:

typedef modulus<c1,c2>::type r;
Return type:Integral Constant.
Precondition:c2::value != 0
Semantics:

Equivalent to

typedef integral_c<
      typeof(c1::value % c2::value)
    , ( c1::value % c2::value )
    > r;
typedef modulus<c1,c2> r;
Return type:Integral Constant.
Precondition:c2::value != 0
Semantics:

Equivalent to

struct r : modulus<c1,c2>::type {};

Complexity

Amortized constant time.

Example

typedef modulus< int_<10>, long_<3> >::type r;
BOOST_MPL_ASSERT_RELATION( r::value, ==, 1 );
BOOST_MPL_ASSERT(( is_same< r::value_type, long > ));

See also

Metafunctions, Numeric Metafunction, numeric_cast, divides, times, plus