Python code minifier (Python)

2014-05-25T16:23:55-07:00

Python recipe 576704 by Dan McDougall (bz2, bzip2, comments, compression, docstring, embedded, gzip, minify, pack, regex, zlib). Revision 16.

Update 05/25/2014: Pyminifier 2.0 has been released and now lives on Github: https://github.com/liftoff/pyminifier (docs are here: http://liftoff.github.io/pyminifier/). The code below is very out-of-date but will be left alone for historical purposes.

Python Minifier: Reduces the size of Python code for use on embedded platforms. Performs the following:

Removes docstrings.
Removes comments.
Removes blank lines.
Minimizes code indentation.
Joins multiline pairs of parentheses, braces, and brackets (and removes extraneous whitespace within).
Preserves shebangs and encoding info (e.g. "# -- coding: utf-8 --")
NEW: Optionally, produces a bzip2 or gzip-compressed self-extracting python script containing the minified source for ultimate minification.

Update 09/23/2010: Version 1.4.1: Fixed an indentation bug when operators such as @ and open parens started a line.

Update 09/18/2010: Version 1.4:

Added some command line options to save the result to an output file.
Added the ability to save the result as a bzip2 or gzip-compressed self-extracting python script (which is kinda neat--try it!).
Updated some of the docstrings to provide more examples of what each function does.

Update 06/02/2010: Version 1.3: Rewrote several functions to use Python's built-in tokenizer module (which I just discovered despite being in Python since version 2.2). This negated the requirement for pyparsing and improved performance by an order of magnitude. It also fixed some pretty serious bugs with dedent() and reduce_operators().

PLEASE POST A COMMENT IF YOU ENCOUNTER A BUG!

Docstring inheritance decorator (Python)

2009-07-28T13:42:32-07:00

Python recipe 576862 by Shai Berger (decorator, descriptor, docstring, inheritance, metaprogramming).

In many cases, a subclass overrides a method in a parent class, just to change its implementation; in such cases, it would be nice to preserve the overridden method's docstring. The decorator below can be used to achieve this without explicit reference to the parent class. It does this by replacing the function with a descriptor, which accesses the parent class when the method is accessed as an attribute.

Using Metaclasses and Class Decorators to Inherit Function Docstrings (Python)

2011-06-11T00:59:35-07:00

Python recipe 577743 by Eric Snow (decorator, decorators, docstring, inheritance, metaclass, metaclasses). Revision 4.

You'll find three different approaches to copying the method's docstring to the overriding method on a child class.

The function decorator approach is limited by the fact that you have to know the class when you call the decorator, so it can't be used inside a class body. However, recipe #577746 provides a function decorator that does not have this limitation.

Inherit method docstrings without breaking decorators or violating DRY (Python)

2013-07-01T02:29:40-07:00

Python recipe 578587 by nikratio (decorator, decorators, docstring, inheritance). Revision 2.

There are several recipes for inheriting method docstrings. However, most of them either violate DRY (and have you repeat the ancestor class name in the method decorator that sets the docstring), or do break decorators that try to access the docstring (because the docstring is only assigned after class creation). This recipe avoids both problems.

Note: This recipe uses the mro method from http://code.activestate.com/recipes/577748-calculate-the-mro-of-a-class/

Viewing embedded pictures within docstrings (Python)

2008-10-15T01:27:26-07:00

Python recipe 576538 by Andre Roberge (docstring, embedded_image, viewer).

Python docstrings are textual information about objects. They can be displayed via help(obj). However, they can not contain images. This recipe allows the inclusion of images (encoded in base 64 in the Python file) inside docstrings in a transparent way. The images are indicated as "docpicture = file_name.ext" inside the docstring, and the encoded data is in variable "file_name" inside the same module.

Inherit Method Docstrings Using Only Function Decorators (Python)

2011-06-26T02:28:55-07:00

Python recipe 577746 by Eric Snow (decorator, decorators, docstring). Revision 3.

This recipe provides a descriptor and a decorator. The decorator will be used on any method in your class to indicate that you want that method to inherit its docstring.

This is useful when you are using abstract bases classes and want a method to have the same docstring as the abstract method it implements.

This recipe uses recipe #577745, the deferred_binder module.

Docstring inheritance class decorator (Python)

2011-11-23T20:12:03-08:00

Python recipe 577102 by Alec Thomas (class, decorator, docstring, inheritance). Revision 2.

Inherits method docstrings from parent classes.