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[Home]plus

Synopsis

template<
      typename T1
    , typename T2
    , typename T3 = integral_c<int,0>
    , ...
    , typename Tn = integral_c<int,0>
    >
struct plus
{
    typedef unspecified type;
};

Description

Returns the sum of its arguments [1].

Definition

#include "boost/mpl/plus.hpp"

Parameters

 Parameter  Requirement  Description  
T1, T2, .., TnA model of Integral Constant

Expression semantics

 Expression  Expression type  Precondition  Semantics  Postcondition 
typedef plus<t1,t2,..,tn>::type sum;A model of Integral ConstantEquivalent to typedef integral_c<typeof(t1::value + t2::value .. + tn::value), t1::value + t2::value .. + tn::value > sum;

Complexity

Amortized constant time.

Example

typedef plus< integral_c<short,-1>, integral_c<long,10> >::type sum;
BOOST_STATIC_ASSERT(sum::value == 9));
BOOST_MPL_ASSERT_IS_SAME(sum::value_type, long);

Notes

[1] The plus metafunction can be (and is expected to be) specialized by user to work on user-defined types that do not satisfy the Integral Constant requirements. The requirements listed here are the ones imposed by the default implementation.

See also

Metafunctions, minus, multiplies, divides, modulus, negate


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Last edited March 10, 2003 6:30 am