Signal

Create new signal.

Attributes

Attribute	Type	Description
receivers	dict = None	Holds a dictionary of {receiverkey (id): weakref(receiver)} mappings.
providing_args	set	A set of the arguments this signal can pass along in a send call.
lock	threading.Lock	A threading lock used to ensure thread-safe access when connecting, disconnecting, or clearing receivers.
use_caching	bool	Enable receiver cache to improve performance by storing receivers for distinct senders.
name	str	Name of signal, used for debugging purposes.
sender_receivers_cache	dict	A cache mapping senders to their associated receivers, implemented as a WeakKeyDictionary if caching is enabled.

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Constructor

Signature

def Signal(
    providing_args: List = None,
    use_caching: bool = False,
    name: str = None
) - > null

Parameters

Name	Type	Description
providing_args	List = None	A list of the arguments this signal can pass along in a send call.
use_caching	bool = False	Enable receiver cache to improve performance for repeated sends.
name	str = None	Name of the signal, used for debugging purposes.

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Methods

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connect()

@classmethod
def connect(
    *args: Any,
    **kwargs: Any
) - > Callable

Connect receiver to sender for signal.

Parameters

Name	Type	Description
*args	Any	Positional arguments, typically the receiver function.
**kwargs	Any	Keyword arguments including sender, weak, dispatch_uid, and retry.

Returns

Type	Description
Callable	The registered receiver function or a decorator if called without a receiver.

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disconnect()

@classmethod
def disconnect(
    receiver: Callable = null,
    sender: Any = null,
    weak: bool = null,
    dispatch_uid: Hashable = null
) - > bool

Disconnect receiver from sender for signal.

Parameters

Name	Type	Description
receiver	Callable = null	The registered receiver to remove.
sender	Any = null	The sender associated with the registration.
weak	bool = null	Deprecated; has no effect on disconnection logic.
dispatch_uid	Hashable = null	The unique identifier used during connection to locate the receiver.

Returns

Type	Description
bool	True if a receiver was successfully disconnected, False otherwise.

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has_listeners()

@classmethod
def has_listeners(
    sender: Any = null
) - > bool

Checks if there are any active receivers registered for the specified sender.

Parameters

Name	Type	Description
sender	Any = null	The sender object to check for listeners.

Returns

Type	Description
bool	True if at least one live receiver is connected, False otherwise.

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send()

@classmethod
def send(
    sender: Any,
    **named: Any
) - > list

Send signal from sender to all connected receivers.

Parameters

Name	Type	Description
sender	Any	The object initiating the signal.
**named	Any	Arbitrary keyword arguments passed directly to the receivers.

Returns

Type	Description
list	A list of tuple pairs: [(receiver, response), ... ] where response may be an Exception.

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