niltype

library1.0.2pypypi✓ verified 85d ago

A small Python library that provides a singleton `Nil` object. This object is designed to represent missing or unset values in scenarios where `None` is a valid and meaningful data value, thus avoiding ambiguity. Currently at version 1.0.2, it's a stable, single-purpose library with infrequent updates.

serialization

pip install niltype

github ↗package ↗

INSTALL

IMPORT

SIG · NILTYPE

niltype

serializationpythonv1.0.2

Install

1.5s avg

Import

11ms

Disk

16MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v1.0.2 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.910 runs

installs and imports cleanly · install 0.0s · import 0.012s · 17.8MB

glibc

py 3.10–3.910 runs

installs and imports cleanly · install 1.5s · import 0.007s · 18MB

16MB installed

● package 16MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Nil

✓ from niltype import Nil

Demonstrates how to import and use the `Nil` singleton to distinguish between a truly missing value (represented by `Nil`) and an intentional `None` value in a function's return, especially useful for API responses or configuration.

from niltype import Nil def get_user_setting(user_id: int, setting_name: str): """Simulates fetching a user setting where Nil means 'not found'.""" if user_id == 1: if setting_name == "theme": return "dark" elif setting_name == "timeout": return None # None is a valid timeout (e.g., no timeout) return Nil # Setting does not exist for this user # Example usage: setting = get_user_setting(1, "theme") print(f"Theme setting: {setting} (is Nil: {setting is Nil})") setting = get_user_setting(1, "timeout") print(f"Timeout setting: {setting} (is Nil: {setting is Nil})") setting = get_user_setting(2, "language") print(f"Language setting: {setting} (is Nil: {setting is Nil})") if setting is Nil: print("\nSetting 'language' for user 2 is missing.") elif setting is None: print("\nSetting 'timeout' is explicitly set to None (no timeout).") else: print(f"\nSetting is {setting}.")

Debug

Known issues

gotchaThe `Nil` object evaluates to `False` in a boolean context, similar to `None`, empty collections, or zero. However, `Nil` is not `None` (`Nil != None`).

fix

Always use identity checks (`if obj is Nil:` or `if obj is not Nil:`) when specifically checking for the `Nil` singleton. Avoid `if not obj:` if you need to distinguish `Nil` from other falsey values.

affects: All versions

gotcha`Nil` is a true singleton, meaning there is only one instance of it throughout your application's lifetime. Any variable assigned `Nil` will reference this single instance.

fix

This is by design and fundamental to `niltype`. It implies `Nil` cannot carry state or attributes specific to a particular missing value context. If you need contextual information, wrap `Nil` in a custom class or use a different pattern.

affects: All versions

Errors

Common errors & fixes

AttributeError: 'NilType' object has no attribute 'some_property'

Attempting to access attributes or methods on a variable that holds `Nil` without first checking for its presence.

fix

Always check `if my_var is not Nil:` before attempting to access properties or methods on `my_var`, as `Nil` has no user-defined attributes.

TypeError: can't concat NilType to str

Passing `Nil` directly to functions or operations that expect a specific data type (e.g., string concatenation, arithmetic operations, database queries) and do not explicitly handle `Nil`.

fix

Implement explicit checks for `Nil` and handle it appropriately (e.g., return early, provide a default value, raise a more specific exception) before passing the variable to type-sensitive operations. For example: `my_str = 'Default' if my_var is Nil else str(my_var)`.

Upgrade

Version history

1.0.2latest on PyPI · released Sep 21, 2024

Audit

Dependencies

No dependency data recorded yet.

Agent activity

4 hits · last 30 days

node

Resources

githubhttps://github.com/tsv1/niltype ↗

packagehttps://pypi.org/project/niltype/ ↗