Treehouse

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!

ydkjs-1.png

Recent Features

  • Chris Coyier’s Favorite CodePen Demos

    David asked me if I'd be up for a guest post picking out some of my favorite Pens from CodePen. A daunting task! There are so many! I managed to pick a few though that have blown me away over the past few months. If you...

  • 5 Ways that CSS and JavaScript Interact That You May Not Know About

    CSS and JavaScript:  the lines seemingly get blurred by each browser release.  They have always done a very different job but in the end they are both front-end technologies so they need do need to work closely.  We have our .js files and our .css, but...

Incredible Demos

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!