Function type R (T1, T2, ..., TN)
boost::signals2::optional_last_value
<R>
int
std::less
<Group>
boost::function
<Signature>
boost::function
<R (const `connection` &, T1, T2, ..., TN)>
boost::signals2::mutex
`boost::signals2::signal_base`
Safe multicast callback.

See the tutorial for more information on how to use the signal class.

Signature
typename Combiner::result_type
Combiner
Group
GroupCompare
SlotFunction
typename `signals2::slot`<Signature, SlotFunction>
ExtendedSlotFunction
typename `signals2::slot`<R (const `connection` &, T1, ..., TN), ExtendedSlotFunction>

Slots of the `extended_slot_type` may be connected to the signal using the `connect_extended` methods. The `extended_slot_type` has an additional `signals2::connection` argument in its signature, which gives slot functions access to their connection to the signal invoking them.

typename SlotFunction::result_type

This is the type returned when dereferencing the input iterators passed to the signal's combiner.

unspecified

The input iterator type passed to the combiner when the signal is invoked.

T1 Exists iff arity == 1
T1 Exists iff arity == 2
T2 Exists iff arity == 2
unsigned
Tn The type of the `signal`'s (n+1)th argument
int N The number of arguments taken by the signal.
const combiner_type&
combiner_type()
const group_compare_type&
group_compare_type()

Initializes the signal to contain no slots, copies the given combiner into internal storage, and stores the given group comparison function object to compare groups.

`this->`empty`()`

signal &&

Move constructor.

`other.`null`()`

Will not throw.

signal &&

Move assignment.

`rhs.`null`()`

Will not throw.

`connection` `const slot_type&` `connect_position at_back`
`connection` `const group_type&` `const slot_type&` `connect_position at_back`

Connects the signal this to the incoming slot. If the slot is inactive, i.e., any of the slots's tracked objects have been destroyed, then the call to connect is a no-op. If the second version of `connect` is invoked, the slot is associated with the given group. The `at` parameter specifies where the slot should be connected: `at_front` indicates that the slot will be connected at the front of the list or group of slots and `at_back` indicates that the slot will be connected at the back of the list or group of slots.

A ``signals2::connection`` object that references the newly-created connection between the signal and the slot; if the slot is inactive, returns a disconnected connection.

This routine meets the strong exception guarantee, where any exception thrown will cause the slot to not be connected to the signal.

Constant time when connecting a slot without a group name or logarithmic in the number of groups when connecting to a particular group.

It is unspecified whether connecting a slot while the signal is calling will result in the slot being called immediately.

`connection` `const extended_slot_type&` `connect_position at_back`
`connection` `const group_type&` `const extended_slot_type&` `connect_position at_back`

The `connect_extended` methods work the same as the `connect` methods, except they take slots of type `extended_slot_type`. This is useful if a slot needs to access the connection between it and the signal invoking it, for example if it wishes to disconnect or block its own connection.

void `const group_type&`
void `const S&`

If the parameter is (convertible to) a group name, any slots in the given group are disconnected. Otherwise, any slots equal to the given slot function are disconnected.

Note, the `slot_func` argument should not be an actual `signals2::slot` object (which does not even support `operator==`), but rather the functor you wrapped inside a `signals2::slot` when you initially made the connection.

Will not throw unless a user destructor or equality operator `==` throws. If either throws, not all slots may be disconnected.

If a group is given, O(lg g) + k where g is the number of groups in the signal and k is the number of slots in the group. Otherwise, linear in the number of slots connected to the signal.

void

Disconnects all slots connected to the signal.

`this->`empty`()`.

If disconnecting a slot causes an exception to be thrown, not all slots may be disconnected.

Linear in the number of slots known to the signal.

May be called at any time within the lifetime of the signal, including during calls to the signal's slots.

bool

`true` if no slots are connected to the signal, and `false` otherwise.

Will not throw.

Linear in the number of slots known to the signal.

Slots can disconnect at any point in time, including while those same slots are being invoked. It is therefore possible that the implementation must search through a list of disconnected slots to determine if any slots are still connected.

std::size_t

The number of slots connected to the signal

Will not throw.

Linear in the number of slots known to the signal.

Slots can disconnect at any point in time, including while those same slots are being invoked. It is therefore possible that the implementation must search through a list of disconnected slots to determine how many slots are still connected.

result_type `arg<0>::type` `arg<1>::type` `...` `arg<N-1>::type`
result_type `arg<0>::type` `arg<1>::type` `...` `arg<N-1>::type`

Invokes the combiner with a `slot_call_iterator` range [first, last) corresponding to the sequence of calls to the slots connected to signal `*this`. Dereferencing an iterator in this range causes a slot call with the given set of parameters `(a1, a2, ..., aN)`, the result of which is returned from the iterator dereference operation.

The result returned by the combiner.

If an exception is thrown by a slot call, or if the combiner does not dereference any slot past some given slot, all slots after that slot in the internal list of connected slots will not be invoked.

Only the slots associated with iterators that are actually dereferenced will be invoked. Multiple dereferences of the same iterator will not result in multiple slot invocations, because the return value of the slot will be cached.

The `const` version of the function call operator will invoke the combiner as `const`, whereas the non-`const` version will invoke the combiner as non-`const`.

combiner_type

A copy of the stored combiner.

Will not throw.

void `const combiner_type&`

Copies a new combiner into the signal for use with future signal invocations.

Will not throw.

void ``signal`&`

Swaps the signal referenced in `this` and `other`.

Will not throw.

bool

`false` for a normal signal, `true` after a signal has been moved from. Null signals are nonfunctional husks left behind after a signal is moved. They may not be invoked or have slots connected to them.

Will not throw.

A null signal may be destroyed, swapped, or move assigned. Also, the following methods may be called on a null signal:

`disconnect` and `disconnect_all_slots`
  no effect
`empty`
  returns `true`
`null`
  returns `true`
`num_slots`
  returns `0`

Any other operation on a null signal is invalid.

void ``signal`<Signature, Combiner, Group, GroupCompare, SlotFunction, ExtendedSlotFunction, Mutex>&` ``signal`<Signature, Combiner, Group, GroupCompare, SlotFunction, ExtendedSlotFunction, Mutex>&`

`x.swap(y)`

Will not throw.