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plus

Synopsis

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

Description

Returns the sum of its arguments.

Header

#include <boost/mpl/plus.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 plus<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 plus<c,c3,...cn>::type r;
typedef plus<c1,...cn> r;
Return type:

Integral Constant.

Semantics:

Equivalent to

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

Complexity

Amortized constant time.

Example

typedef plus< int_<-10>, int_<3>, long_<1> >::type r;
BOOST_MPL_ASSERT_RELATION( r::value, ==, -6 );
BOOST_MPL_ASSERT(( is_same< r::value_type, long > ));

See also

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