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minus

Synopsis

template<
      typename T1
    , typename T2
    , typename T3 = unspecified
    ...
    , typename Tn = unspecified
    >
struct minus
{
    typedef unspecified type;
};

Description

Returns the difference of its arguments.

Header

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

Model of

Numeric Metafunction

Parameters

Parameter Requirement Description
T1, T2,... Tn 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,c2,... cn:

typedef minus<c1,...cn>::type r; 
Return type:Integral Constant.
Semantics:

Equivalent to

typedef integral_c<
      typeof(c1::value - c2::value)
    , ( c1::value - c2::value )
    > c;
    
typedef minus<c,c3,...cn>::type r; 
typedef minus<c1,...cn> r;
Return type:Integral Constant.
Semantics:

Equivalent to

struct r : minus<c1,...cn>::type {};

Complexity

Amortized constant time.

Example

typedef minus< int_<-10>, int_<3>, long_<1> >::type r;
BOOST_MPL_ASSERT_RELATION( r::value, ==, -14 );
BOOST_MPL_ASSERT(( is_same< r::value_type, long > ));

See also

Arithmetic Operations, Numeric Metafunction, numeric_cast, plus, negate, times