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Front Page / Data Types / Concepts / Integral Constant |
An Integral Constant is a holder class for a compile-time value of an integral type. Every Integral Constant is also a nullary Metafunction, returning itself. An integral constant object is implicitly convertible to the corresponding run-time value of the wrapped integral type.
In the following table and subsequent specifications, n is a model of Integral Constant.
Expression | Type | Complexity |
---|---|---|
n::value_type | An integral type | Constant time. |
n::value | An integral constant expression | Constant time. |
n::type | Integral Constant | Constant time. |
next<n>::type | Integral Constant | Constant time. |
prior<n>::type | Integral Constant | Constant time. |
n::value_type const c = n() | Constant time. |
Expression | Semantics |
---|---|
n::value_type | A cv-unqualified type of n::value. |
n::value | The value of the wrapped integral constant. |
n::type | is_same<n::type,n>::value == true. |
next<n>::type | An Integral Constant c of type n::value_type such that c::value == n::value + 1. |
prior<n>::type | An Integral Constant c of type n::value_type such that c::value == n::value - 1. |
n::value_type const c = n() | c == n::value. |