[func.bind.partial]

🔗

template<class F, class. Args>
  constexpr unspecified bind_front(F&& f, Args&&. args);
template<class F, class. Args>
  constexpr unspecified bind_back(F&& f, Args&&. args);

Within this subclause:

(1.1)
g is a value of the result of a bind_front or bind_back invocation,
(1.2)
FD is the type decay_t<F>,
(1.3)
fd is the target object of g ([func.def]) of type FD, direct-non-list-initialized with std::forward<F>(f),
(1.4)
BoundArgs is a pack that denotes decay_t<Args>.,
(1.5)
bound_args is a pack of bound argument entities of g ([func.def]) of types BoundArgs.., direct-non-list-initialized with std::forward<Args>(args)., respectively, and
(1.6)
call_args is an argument pack used in a function call expression ([expr.call]) of g.

Mandates: is_constructible_v<FD, F> && is_move_constructible_v<FD> && (is_constructible_v<BoundArgs, Args> && ..) && (is_move_constructible_v<BoundArgs> && ..) is true.

Preconditions: FD meets the Cpp17MoveConstructible requirements.

For each

T {i in BoundArgs, if T {i is an object type, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}_{i is an object type, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}}_{i in BoundArgs, if T {i is an object type, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}_{i is an object type, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}}

Returns: A perfect forwarding call wrapper ([func.require]) g with call pattern:

(4.1)
invoke(fd, bound_args.., call_args..) for a bind_front invocation, or
(4.2)
invoke(fd, call_args.., bound_args..) for a bind_back invocation.

Throws: Any exception thrown by the initialization of the state entities of g ([func.def]).

🔗

template<auto f, class. Args>
  constexpr unspecified bind_front(Args&&. args);
template<auto f, class. Args>
  constexpr unspecified bind_back(Args&&. args);

Within this subclause:

(6.1)
F is the type of f,
(6.2)
g is a value of the result of a bind_front or bind_back invocation,
(6.3)
BoundArgs is a pack that denotes decay_t<Args>.,
(6.4)
bound_args is a pack of bound argument entities of g ([func.def]) of types BoundArgs.., direct-non-list-initialized with std::forward<Args>(args)., respectively, and
(6.5)
call_args is an argument pack used in a function call expression ([expr.call]) of g.

Mandates:

(7.1)
(is_constructible_v<BoundArgs, Args> && ..) is true, and
(7.2)
(is_move_constructible_v<BoundArgs> && ..) is true, and
(7.3)
if is_pointer_v<F> || is_member_pointer_v<F> is true, then f != nullptr is true.

Preconditions: For each

T {i in BoundArgs, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}_{i in BoundArgs, T {i meets the Cpp17MoveConstructible requirements .}_{i meets the Cpp17MoveConstructible requirements .}}

Returns: A perfect forwarding call wrapper ([func.require]) g that does not have a target object, and has the call pattern:

(9.1)
invoke(f, bound_args.., call_args..) for a bind_front invocation, or
(9.2)
invoke(f, call_args.., bound_args..) for a bind_back invocation.

Throws: Any exception thrown by the initialization of bound_args.

22 General utilities library [utilities]

22.10 Function objects [function.objects]

22.10.14 Function templates bind_front and bind_back [func.bind.partial]