swoc::meta::let< T > Struct Template Reference

#include <swoc_meta.h>

Collaboration diagram for swoc::meta::let< T >:

Public Types
using	self_type = let

Public Member Functions
	let (self_type const &that)=delete
self_type &	operator= (self_type const &)=delete
	let (T &var, T const &value)
	let (T &var, T &&value)

Public Attributes
T &	_var
	Reference to scoped variable.
T	_value
	Original value.

Detailed Description

template<typename T>
struct swoc::meta::let< T >

Scoped value change.

The purpose of this class is to change the value of a variable in a scope and then change it back when the scope is exited. The old value will be moved to a cache variable and then moved back when the instance is destructed. This is very useful to temporarily tweak global variables which having to know what the current value is.

{
  let save(var, value);
  // var now has value.
}
// var now has original value.

Template Parameters

T	Type of variable to scope.

Definition at line 257 of file swoc_meta.h.

Member Typedef Documentation

self_type

template<typename T>

using swoc::meta::let< T >::self_type = let

Definition at line 258 of file swoc_meta.h.

Constructor & Destructor Documentation

let() [1/2]

template<typename T>

swoc::meta::let< T >::let	(	T &	var,
		T const &	value )

Construct a scope.

Parameters

var	Variable to scope.
value	temporary value to assign.

Definition at line 283 of file swoc_meta.h.

let() [2/2]

template<typename T>

swoc::meta::let< T >::let	(	T &	var,
		T &&	value )

Construct a scope.

Parameters

var	Variable to scope.
value	temporary value to assign.

Definition at line 286 of file swoc_meta.h.

~let()

template<typename T>

swoc::meta::let< T >::~let

(

)

Definition at line 290 of file swoc_meta.h.

Member Data Documentation

_value

template<typename T>

T swoc::meta::let< T >::_value

Original value.

Definition at line 264 of file swoc_meta.h.

_var

template<typename T>

T& swoc::meta::let< T >::_var

Reference to scoped variable.

Definition at line 263 of file swoc_meta.h.

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The documentation for this struct was generated from the following file:

• swoc_meta.h