Fix Python – Correct way to define Python source code encoding

Question

Asked By – Oli

PEP 263 defines how to declare Python source code encoding.

Normally, the first 2 lines of a Python file should start with:

#!/usr/bin/python
# -*- coding: <encoding name> -*-

But I have seen a lot of files starting with:

#!/usr/bin/python
# -*- encoding: <encoding name> -*-

=> encoding instead of coding.

So what is the correct way of declaring the file encoding?

Is encoding permitted because the regex used is lazy? Or is it just another form of declaring the file encoding?

I’m asking this question because the PEP does not talk about encoding, it just talks about coding.

Now we will see solution for issue: Correct way to define Python source code encoding


Answer

Check the docs here:

“If a comment in the first or second line of the Python script matches the regular expression coding[=:]\s*([-\w.]+), this comment is processed as an encoding declaration”

“The recommended forms of this expression are

# -*- coding: <encoding-name> -*-

which is recognized also by GNU Emacs, and

# vim:fileencoding=<encoding-name>

which is recognized by Bram Moolenaar’s VIM.”

So, you can put pretty much anything before the “coding” part, but stick to “coding” (with no prefix) if you want to be 100% python-docs-recommendation-compatible.

More specifically, you need to use whatever is recognized by Python and the specific editing software you use (if it needs/accepts anything at all). E.g. the coding form is recognized (out of the box) by GNU Emacs but not Vim (yes, without a universal agreement, it’s essentially a turf war).

This question is answered By – Rafał Dowgird

This answer is collected from stackoverflow and reviewed by FixPython community admins, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0