all Python 3gcfunction

gc.is_tracked()

introspection

Checks whether the cyclic garbage collector tracks an object. Numbers and strings are not tracked; lists and class instances are.

Syntax

gc.is_tracked(obj)

The collector may 'untrack' non-atomic objects to save work, and the rules depend on the version: an empty dict or a tuple of numbers gives False on some versions and True on others (3.14 and 3.15 changed them). So tests should rely on is_tracked only for stable cases — atoms and lists. Tracking is not lifetime: an untracked number is still freed by reference counting as usual.

Examples

import gc
class P:
    pass
print(gc.is_tracked(42), gc.is_tracked('text'))  # → False False
print(gc.is_tracked([]), gc.is_tracked(P()))  # → True True
print(gc.is_tracked({}))  # → ? False до 3.13, True с 3.14

gc.is_tracked()

Syntax

Examples

See also