Release Notes¶

absence 1.2 (2026-08-07)¶

Add AbsenceCell[T] immutable container wrapping Absential[T] with a rich API for conditional extraction, evaluation, transformation, chaining, and Optional bridging.
Add adapt_dataclass() helper to bridge CLI dataclasses (which use None for not-provided) to functions with Absential[T] parameters by omitting fields that match a configurable skip value.
Add is_present() predicate as positive-form counterpart to is_absent(). Returns TypeIs[T] to enable type narrowing without negation.

Internal improvement to use classcore.finalize_module rather than the deprecated classcore.reclassify_modules.

Convert Absential to proper type alias and to use separately-declared type variable. (Addresses Pyright complaints.)

Add AbsenceFactory class for creating package-specific absence sentinels. Each instance evaluates to False in boolean contexts, has unique identity, and supports customizable string representations.
Add Absential type alias for annotating values that may be absent, supporting clear type hints for optional parameters and return values where None is a valid value.
Add absent sentinel, a falsey singleton that represents absence in contexts where None might be a valid value. The sentinel maintains global uniqueness, supports proper equality comparison, and can be installed as a builtin.
Add is_absent and is_absence predicates for type-safe checking of absence sentinels. These can distinguish between the global sentinel and factory-produced sentinels, and support installation as builtins.
Add optional builtin installation support, allowing the absent sentinel and its predicates to be used without imports, similar to None. Supports custom names and selective installation of components.