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identity Structure

A struct that provides a type definition as the template parameter.

template<class Type>
   struct identity {
      typedef Type type;
      Type operator()(const Type& _Left) const;
   };

Parameters

Parameter

Description

_Left

The value to identify.

Remarks

The class contains the public type definition type, which is the same as the template parameter Type. It is used in conjunction with template function forward to ensure that a function parameter has the desired type.

For compatibility with older code, the class also defines the identity function operator() which returns its argument _Left.

Requirements

Header: <utility>

Namespace: std

See Also

Reference

<utility>