named

1.4.2 verified Mon Apr 27 auth: no python

A Python library providing named types (newtypes) with runtime validation and type-checking support. Current version 1.4.2, requires Python ≥3.8, follows semantic versioning with regular releases.

pip install named

Common errors

error ImportError: cannot import name 'Named' from 'named' ↓

cause The correct import is `import named` then use `named.Named`; there is no direct `from named import Named`.

fix

Use import named and reference named.Named.

error TypeError: 'Named' object does not support item assignment ↓

cause Named objects are immutable and do not support setting attributes after creation.

fix

Create a new named instance instead of modifying existing one.

Warnings

gotcha Named types are immutable after creation: you cannot reassign the value attribute. ↓

fix Create a new instance with the desired value instead of modifying an existing one.

gotcha The `Named` class does not support custom `__init__` methods; initialization is handled by the parent class. Overriding `__init__` may break validation. ↓

fix Use class methods or properties to add custom behavior without overriding `__init__`.

Imports

named
```
import named
```
Main package, all functions and classes are accessed from the top-level module.

Quickstart

Define a named type by subclassing `Named`. The subclass provides runtime type checking and can be used with type hints.

import named

# Define a named type for UserId
class UserId(named.Named):
    pass

# Create an instance with validation
uid = UserId(42)
print(uid)  # UserId(42)

# Access the underlying value
print(uid.value)  # 42