std::experimental::scope_exit<EF>::scope_exit
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std::experimental::scope_exit
Member functions
scope_exit::scope_exit
Modifiers
template< class Fn >
explicit scope_exit( Fn&& fn ) noexcept(/*see below*/);
(1)
(library fundamentals TS v3)
explicit scope_exit( Fn&& fn ) noexcept(/*see below*/);
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
EFdoes not meet the requirements of MoveConstructible, or - std::is_nothrow_move_constructible_v <EF> is false and
EFdoes not meet the requirements of CopyConstructible.
Contents
[edit] Parameters
fn
-
function or function object used for initializing the stored
EF
other
-
scope_exit to move from
[edit] 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&>)
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>)
std::is_nothrow_copy_constructible_v <EF>)
[edit] Example
This section is incomplete
Reason: no example
Reason: no example