qualname

library0.1.0pypypi✓ verified 24d ago

The `qualname` Python module emulates the `__qualname__` attribute for classes and methods in older Python versions (specifically pre-Python 3.3). Introduced in PEP 3155, `__qualname__` provides a 'qualified name' including the full dotted path to an object within its module, which is particularly useful for nested definitions. This library achieves this by performing source code inspection and abstract syntax tree (AST) parsing, which means the source file must be available at runtime. The current version is 0.1.0, and its release cadence is infrequent, as its primary utility lies in supporting older Python environments.

serialization

pip install qualname

github ↗package ↗

INSTALL

IMPORT

SIG · QUALNAME

qualname

serializationpythonv0.1.0

Install

2.6s avg

Import

23ms

Disk

17MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v0.1.0 · 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 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.024s · 19.2MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 2.6s · import 0.022s · 20MB

17MB installed

● package 17MB

Code

Verified usage

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

qualname

✓ from qualname import qualname

Demonstrates how to use the `qualname()` function to retrieve the qualified name for classes, methods, and nested functions. On Python 3.3+, native `__qualname__` is used, otherwise the library's emulation is applied.

import sys from qualname import qualname class Outer: def method_a(self): pass class Inner: def method_b(self): pass def top_level_func(): def nested_func(): pass return nested_func # For Python < 3.3, this library provides __qualname__ functionality # On Python 3.3+, objects already have __qualname__ print(f"Python Version: {sys.version.split(' ')[0]}") print(f"Outer.__qualname__: {qualname(Outer)}") print(f"Outer.method_a.__qualname__: {qualname(Outer.method_a)}") print(f"Outer.Inner.__qualname__: {qualname(Outer.Inner)}") print(f"Outer.Inner.method_b.__qualname__: {qualname(Outer.Inner.method_b)}") nested_f = top_level_func() print(f"top_level_func.__qualname__: {qualname(top_level_func)}") print(f"nested_f.__qualname__: {qualname(nested_f)}")

Debug

Known issues

gotchaThe library relies on source code inspection, meaning the source file must be available for `qualname()` to work. For objects like built-in types, or when the source cannot be determined (e.g., in some dynamically generated code), it may fall back to `__name__` or raise errors.

fix

Ensure the object's source file is accessible. For built-in types, directly use `__name__` or `str(obj)`.

affects: <0.1.0

gotchaThis library is primarily intended for Python versions older than 3.3. In Python 3.3 and later, the `__qualname__` attribute is a built-in feature of classes and functions, making this library redundant for those versions.

fix

On Python 3.3+, simply access `obj.__qualname__` directly. No need to import or use the `qualname` library.

affects: >=3.3

gotchaThe `__qualname__` attribute (whether native or emulated by this library) provides the dotted path within a module but does NOT include the module name itself. Users often expect a 'fully qualified name' that includes the module (e.g., `my_module.MyClass.my_method`).

fix

To get a fully qualified name, combine `obj.__module__` and `qualname(obj)` (or `obj.__qualname__` on Python 3.3+): `f'{obj.__module__}.{qualname(obj)}'`.

affects: *

gotchaFor inherited methods, `__qualname__` will report the qualified name from the class where the method was *defined*, not necessarily the class from which it is being accessed if the method is not overridden. This can lead to unexpected results if you expect `__qualname__` to always reflect the current class hierarchy.

fix

Be aware of inheritance behavior. If you need the `__qualname__` to reflect a child class for an inherited method, the method must be explicitly overridden in the child class.

affects: *

Errors

Common errors & fixes

ModuleNotFoundError: No module named 'qualname'

The `qualname` package has not been installed in the current Python environment.

fix

pip install qualname

AttributeError: type object 'MyClass' has no attribute '__qualname__'

In Python versions prior to 3.3, the `__qualname__` attribute does not exist natively, and the `qualname` library was not imported to backport this functionality.

fix

Add `import qualname` at the beginning of your script to enable the `__qualname__` emulation for classes and functions defined thereafter.

TypeError: object is not a class, function, or method

The `qualname.qualname()` function is designed to retrieve the qualified name only for class objects, function objects, or method objects, and raises an error for other types (e.g., modules, variables, instances).

fix

Ensure that the argument passed to `qualname.qualname()` is a class, a function, or a method object.

TypeError: <built-in function/method name> is a built-in function/method

The `qualname` library relies on inspecting the source code, which is not available for built-in Python objects, leading to an error from the underlying `inspect.getsource` call.

fix

The `qualname` library cannot determine qualified names for built-in objects, as their source code is not accessible; this functionality is intended for user-defined Python objects.

Upgrade

Version history

0.1.0latest on PyPI · released Apr 11, 2015

Audit

Dependencies

No dependency data recorded yet.

Agent activity

7 hits · last 30 days

node

Resources

githubhttps://github.com/wbolster/qualname ↗

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