Style and Naming¶
Style matters!
PEP 8 reminder¶
PEP 8 (Python Enhancement Proposal 8): https://www.python.org/dev/peps/pep-0008/
Is the “official” style guide for Python code.
Strictly speaking, you only need to follow it for code in the standard library.
But style matters – consistent style makes your code easier to read and understand.
And everyone in the community has accepted PEP as the Python style guide.
So follow PEP 8
Exception: if you have a company style guide – follow that instead.
Try the “pycodestyle” module on your code:
$ python3 -m pip install pycodestyle
$ pycodestyle my_python_file
Try it now – really!
Note that ideally you have a linter installed in your editor that yells at you if you violate PEP8 – no need to run pycodestyle if it’s already in your editor.
See: Text Editors Only for suggestions on editors and configuration.
Naming things…¶
It matters what names you give your variables.
Python has rules about what it allows.
PEP8 has rules for style: capitalization, and underscores and all that.
But you still get to decide within those rules.
So use names that make sense to the reader.
Naming Guidelines¶
Whenever possible, use strong, unambiguous names that relate to a concept in the business area applicable for your program.
For example, cargo_weight is probably better than item_weight, current_fund_price is better than value.
Only use single-letter names for things with limited scope: indexes and the like:
for i, item in enumerate(a_sequence):
do_something(i, item)
But don’t use a name like “item”, when there is a meaning to what the item is:
for name in all_the_names:
do_something_with(name)
Use plurals for collections of things:
names = ['Fred', 'George', ...]
And then singular for a single item in that collection:
for name in names:
...
Do re-use names when the use is essentially the same, and you don’t need the old one:
line = line.strip()
line = line.replace(",", " ")
....
Here’s a nice talk about naming: