bslmf_removevolatile

Detailed Description

Outline

• Purpose
• Classes
• Description
  • Usage
    • Example 1: Removing the volatile-Qualifier of a Type

Purpose

Provide a meta-function for removing volatile-qualifier.

Classes

• bsl::remove_volatile: meta-function for removing volatile-qualifier
• bsl::remove_volatile_t: alias to the return type of the meta-function

See also

bslmf_addvolatile

Description

This component defines a meta-function, bsl::remove_volatile and declares an bsl::remove_volatile_t alias to the return type of the bsl::remove_volatile, that may be used to remove any top-level volatile-qualifier from a type.

bsl::remove_volatile and bsl::remove_volatile_t meet the requirements of the remove_volatile template defined in the C++11 standard [meta.trans.cv].

Usage

In this section we show intended use of this component.

Example 1: Removing the volatile-Qualifier of a Type

Suppose that we want to remove any volatile-qualifier from a particular type.

First, we create two typedefs – a volatile-qualified type (MyVolatileType) and the same type without the volatile-qualifier (MyType):

 typedef int          MyType;
 typedef volatile int MyVolatileType;

Now, we remove the volatile-qualifier from MyVolatileType using bsl::remove_volatile and verify that the resulting type is the same as MyType:

 assert(true == (bsl::is_same<bsl::remove_volatile<MyVolatileType>::type,
                                                           MyType>::value));

Finally, if the current compiler supports alias templates C++11 feature, we remove a volatile-qualifier from MyVolatileType using bsl::remove_volatile_t and verify that the resulting type is the same as MyType:

 #ifdef BSLS_COMPILERFEATURES_SUPPORT_ALIAS_TEMPLATES
   assert(true ==
       (bsl::is_same<bsl::remove_volatile_t<MyVolatileType>, MyType>::value));
 #endif

Note, that the bsl::remove_volatile_t avoids the ::type suffix and typename prefix when we want to use the result of the bsl::remove_const meta-function in templates.