jangada.mixin.Identifiable

class jangada.mixin.Identifiable

Bases: object

Mixin that adds a globally unique, write-once UUID identifier.

Provides each instance with a unique ID that cannot be changed after initialization. Instances are tracked in a weak-reference registry, allowing lookup by ID while permitting garbage collection.

The ID is a UUID v4 (randomly generated) stored as a 32-character hexadecimal string. It is not included when copying objects (copiable=False).

Attributes:

idstr

A unique 32-character hexadecimal UUID v4 identifier. Write-once, auto-generated if not provided, and not copied.

See also

Taggable

Symbolic identifier for namespace access

SerializableProperty

Property descriptor used for id

Notes

Equality Semantics

Two Identifiable objects are equal if they have the same ID. This implements value equality; for identity equality use is. Subclasses can override __eq__ for content-based equality.

Hash Consistency

Hash is based solely on ID, ensuring objects can be used in sets and as dictionary keys. Hash remains consistent even if other attributes change.

Weak References

The registry uses weak references, so instances can be garbage collected even while registered. After garbage collection, get_instance() will return None for that ID.

Copy Behavior

The ID is not copied when using copy.copy() or serialization with is_copy=True. Each copy gets a new, unique ID.

Thread Safety

The registry is not thread-safe. Concurrent access from multiple threads may require external synchronization.

Examples

Basic usage:

class Component(Identifiable):
    pass

comp = Component()
print(comp.id)  # '3a5f8e2c1b9d4f7a...'

Lookup by ID:

comp_id = comp.id
retrieved = Identifiable.get_instance(comp_id)
assert retrieved is comp

Hash and equality based on ID:

comp1 = Component()
comp2 = Component()

# Different IDs
assert comp1 != comp2
assert hash(comp1) != hash(comp2)

# Can use in sets and dicts
components = {comp1, comp2}

Write-once protection:

comp = Component()
original_id = comp.id

# Cannot change ID
comp.id = 'different-id'  # Raises AttributeError

__init__(*args, **kwargs)

Methods

__delattr__(name, /)	Implement delattr(self, name).
__dir__(/)	Default dir() implementation.
__eq__(other)	Compare equality based on ID.
__format__(format_spec, /)	Default object formatter.
__ge__(value, /)	Return self>=value.
__getattribute__(name, /)	Return getattr(self, name).
__getstate__(/)	Helper for pickle.
__gt__(value, /)	Return self>value.
__hash__()	Compute hash based on ID.
__init__(*args, **kwargs)
__init_subclass__	This method is called when a class is subclassed.
__le__(value, /)	Return self<=value.
__lt__(value, /)	Return self<value.
__ne__(value, /)	Return self!=value.
__reduce__(/)	Helper for pickle.
__reduce_ex__(protocol, /)	Helper for pickle.
__repr__(/)	Return repr(self).
__sizeof__(/)	Size of object in memory, in bytes.
__str__(/)	Return str(self).
__subclasshook__	Abstract classes can override this to customize issubclass().
get_instance(id_)	Retrieve an Identifiable instance by its ID.

Attributes

__annotations__
_instances
id	Globally unique identifier (UUID v4).