std::experimental::scope_exit<EF>::scope_exit

 

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Library fundamentals v3

experimental::scope_exit

experimental::scope_fail

experimental::scope_success

experimental::unique_resource

 

std::experimental::scope_exit

Member functions

scope_exit::scope_exit

scope_exit::~scope_exit

Modifiers

scope_exit::release

Deduction guides

 

template< class Fn > explicit scope_exit( Fn&& fn ) noexcept(/*see below*/);	(1)	(library fundamentals TS v3)
scope_exit( scope_exit&& other ) noexcept(/*see below*/);	(2)	(library fundamentals TS v3)
scope_exit( const scope_exit& ) = delete;	(3)	(library fundamentals TS v3)

Creates a scope_exit from a function, a function object or another scope_exit.

1) Initializes the exit function with a function or function object. The constructed scope_exit is active.

If Fn is not an lvalue reference type and std::is_nothrow_constructible_v<EF, Fn> is true, the stored EF is initialized with std::forward<Fn>(fn); otherwise it is initialized with fn.

If initialization of the stored EF throws an exception, calls fn().

This overload participates in overload resolution only if std::is_same_v<std::remove_cvref_t<Fn>, scope_exit> is false and std::is_constructible_v<EF, Fn> is true.

The program is ill-formed if function call expression fn() is ill-formed.

The behavior is undefined if calling fn() throws an exception or results in undefined behavior, even if fn has not been called.

2) Move constructor. Initializes the stored EF with the one in other. The constructed scope_exit is active if and only if other is active before the construction.

If std::is_nothrow_move_constructible_v<EF> is true, initializes stored EF (denoted by exitfun) with std::forward<EF>(other.exitfun), otherwise initializes it with other.exitfun.

After successful move construction, other.release() is called and other becomes inactive.

This overload participates in overload resolution only if std::is_nothrow_move_constructible_v<EF> is true or std::is_copy_constructible_v<EF> is true.

The behavior is undefined if

• std::is_nothrow_move_constructible_v<EF> is true and EF does not meet the requirements of MoveConstructible, or
• std::is_nothrow_move_constructible_v<EF> is false and EF does not meet the requirements of CopyConstructible.

3) scope_exit is not CopyConstructible.

Parameters

fn	-	function or function object used for initializing the stored EF
other	-	scope_exit to move from

Exceptions

Any exception thrown during the initialization of the stored EF.

1)

noexcept specification:  

noexcept(std::is_nothrow_constructible_v<EF, Fn> ||
         std::is_nothrow_constructible_v<EF, Fn&>)

2)

noexcept specification:  

noexcept(std::is_nothrow_move_constructible_v<EF> ||
         std::is_nothrow_copy_constructible_v<EF>)

See also

release

makes the scope_exit inactive (public member function)