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std::experi...::scope_exit(3) C++ Standard Libarystd::experi...::scope_exit(3)

NAME
       std::experimental::scope_exit - std::experimental::scope_exit

Synopsis
	  Defined in header <experimental/scope>
	  template<class EF>			  (library fundamentals	TS v3)
	  class	scope_exit;

	  The  class  template scope_exit is a general-purpose scope guard in-
       tended to call its
	  exit function	when a scope is	exited.

	  scope_exit is	not CopyConstructible, CopyAssignable or  MoveAssigna-
       ble, however, it
	  may  be  MoveConstructible if	EF meets some requirements, which per-
       mits wrapping a
	  scope_exit into another object.

	  A scope_exit may be either active, i.e. calls	its exit  function  on
       destruction, or
	  inactive,  i.e.  does	nothing	on destruction.	A scope_exit is	active
       after constructed
	  from an exit function.

	  A scope_exit can become inactive by calling release()	on  it	either
       manually	or
	  automatically	 (by the move constructor). An inactive	scope_exit may
       also be obtained
	  by initializing with another inactive	scope_exit. Once a  scope_exit
       is inactive, it
	  cannot become	active again.

	  A  scope_exit	 effectively holds an EF and a bool flag indicating if
       it is active.

Template parameters
	  EF			-		    type of stored exit	 func-
       tion

Type requirements
	  -
	  EF shall be either:

	    * a	Destructible FunctionObject type
	    * an lvalue	reference to FunctionObject
	    * an lvalue	reference to function
	  -
	  Calling  an  lvalue  of std::remove_reference_t<EF> with no argument
       shall be
	  well-formed.

Member functions
	  constructor	constructs a new scope_exit
			(public	member function)
			calls the exit function	when the scope	is  exited  if
       the scope_exit is
	  destructor	active,	then destroys the scope_exit
			(public	member function)
	  operator=	scope_exit is not assignable
	  [deleted]	(public	member function)

Modifiers
	  release	makes the scope_exit inactive
			(public	member function)

	 Deduction guides

Notes
	  Constructing	a scope_exit of	dynamic	storage	duration might lead to
       unexpected
	  behavior.

	  If the EF stored in a	scope_exit object refers to a  local  variable
       of the function
	  where	 it  is	 defined,  e.g., as a lambda capturing the variable by
       reference, and that
	  variable is used as a	return operand in that function, that variable
       might have
	  already been returned	when  the  scope_exit's	 destructor  executes,
       calling the exit
	  function. This can lead to surprising	behavior.

Example
	   This	section	is incomplete
	   Reason: no example

See also
			 wraps a function object and invokes it	on exiting the
       scope through
	  scope_fail	 an exception
			 (class	template)
	  scope_success	 wraps a function object and invokes it	on exiting the
       scope normally
			 (class	template)
	  default_delete default deleter for unique_ptr
	  (C++11)	 (class	template)

http://cppreference.com		  2022.07.31	 std::experi...::scope_exit(3)

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