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conditional Class

 

The latest version of this topic can be found at conditional Class.

Selects one of two types, depending on the specified condition.

Syntax

template <bool B, class T1, class T2>  
struct conditional;

template <bool _Test, class _T1, class _T2>  
using conditional_t = typename conditional<_Test, _T1, _T2>::type;

Parameters

B
The value that determines the selected type.

T1
The type result when B is true.

T2
The type result when B is false.

Remarks

The template member typedef conditional<B, T1, T2>::type evaluates to T1 when B evaluates to true, and evaluates to T2 when B evaluates to false.

Requirements

Header: <type_traits>

Namespace: std

See Also

<type_traits>