{"categories":[{"label":"Python Modules","url":"https://skillfed.io/packages/category/software-development-libraries-python-modules/18"}],"enrichment":{"capability":"Creates singleton sentinel objects that represent special terminating conditions or symbolic meanings, allowing you to distinguish missing values from falsy ones like None, 0, or False.","skillfed_tags":["singleton-pattern","design-pattern"],"use_cases":["Distinguish missing dictionary entries from stored None or falsy values using dict.get() with a sentinel default.","Set meaningful default values in dict.setdefault() when all other values (including 0, False, None) are valid.","Mark leaf nodes or terminal states in tree or graph structures with a singleton that can be checked with `is`.","Create self-documenting API return values that signal special conditions without overloading None or raising exceptions."],"what_it_does":"Sentinel creates lightweight singleton objects that act as unique markers, similar to Python's built-in None, NotImplemented, and Ellipsis. Each sentinel is the only instance of its own anonymous class, making it safe to compare with `is` rather than `==`. This is useful when you need to distinguish a truly missing or unset value from legitimate falsy values like 0, False, or None that might actually be stored in a data structure.\n\nThe package supports pickling, deepcopy, and allows you to attach custom methods and attributes to sentinels. It has an optional feature (via the varname extra) to infer sentinel names from assignment expressions, reducing boilerplate. With zero runtime dependencies and support for Python 3.6+, it's a minimal utility for cases where None alone is insufficient as a sentinel.","worth_installing":"Yes, if you need sentinel objects for a small, self-contained utility. The package is stable, has no dependencies, and solves a real problem cleanly. However, the abandoned status (last commit 2022-07-23) means no future maintenance or Python 4 support\u2014acceptable for a mature, narrow-scope library but worth noting if you depend on active upstream development."},"id":"sentinel","links":{"html":"https://skillfed.io/packages/sentinel","md":"https://skillfed.io/packages/sentinel.md","pypi":"https://pypi.org/project/sentinel/"},"maintenance":{"status":"abandoned"},"meta":{"latest_release":"2022-07-23","license_spdx":null,"license_treatment":"permissive","name":"sentinel","python_support":"supports_current","summary":"Create sentinel objects, akin to None, NotImplemented, Ellipsis"},"popularity":{"monthly_downloads":146455,"position":11098,"tier":"top_15000"},"security":{"n_vulnerabilities":0},"version":"1.0.0"}