Get Class Methods with Python

By  on  

As a newbie to the excellent world of Python development, I'm not always familiar with the methods provided by imported classes.  Oftentimes these classes are well-documented but in the case that methods aren't documented, I found the dir function useful for getting a list of methods:

# dir({object})
dir(difflib)

"""
Returns:

['Differ', 'HtmlDiff', 'IS_CHARACTER_JUNK', 'IS_LINE_JUNK', 'Match', 'SequenceMatcher', '__all__', '__builtins__', '__doc__', '__file__', '__name__', '__package__', '_calculate_ratio', '_count_leading', '_file_template', '_legend', '_mdiff', '_namedtuple', '_styles', '_table_template', '_test', 'context_diff', 'get_close_matches', 'heapq', 'ndiff', 'reduce', 'restore', 'unified_diff']

"""

The snippet above does exactly what you would expect -- provides a list of method names for the viewing!

Recent Features

  • By
    7 Essential JavaScript Functions

    I remember the early days of JavaScript where you needed a simple function for just about everything because the browser vendors implemented features differently, and not just edge features, basic features, like addEventListener and attachEvent.  Times have changed but there are still a few functions each developer should...

  • By
    Write Simple, Elegant and Maintainable Media Queries with Sass

    I spent a few months experimenting with different approaches for writing simple, elegant and maintainable media queries with Sass. Each solution had something that I really liked, but I couldn't find one that covered everything I needed to do, so I ventured into creating my...

Incredible Demos

  • By
    MooTools: Set Style Per Media

    I'd bet one of the most used MooTools methods is the setStyle() method, which allows you to set CSS style declarations for an element. One of the limitations of MooTools' setStyle() method is that it sets the specific style for all medias.

  • By
    Create a Clearable TextBox with the Dojo Toolkit

    Usability is a key feature when creating user interfaces;  it's all in the details.  I was recently using my iPhone and it dawned on my how awesome the "x" icon is in its input elements.  No holding the delete key down.  No pressing it a...

Discussion

  1. hwiechers

    Isn’t this normall done with dir(difflib)?

    • That does the same thing but alphabetizes the result. Thanks for mentioning that!

  2. Jasper

    It does not do the same thing. dir(my_object) will show you everything you can do on the instance, including methods on the class, and superclasses. __dict__ will only show you the unique things that belong to the object, which isn’t very many.

    • Thanks for the additional information Jasper! I’ve updated my post!

  3. Marcin

    You can also use bpython shell which is a nice alternative to ipython and standard python ones. It has auto-completion which displays all available methods and attributes on any object. It can be installed in virtualenv with pip install bpython.

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!