os.path.isfile

[Chris Angelico]

On Mon, Feb 13, 2017 at 11:11 AM, Chris Angelico <rosuav at gmail.com> wrote:
> The string "\t" gets shown in the repr as "\t". It is a string
> consisting of one character, U+0009, a tab. The string r"\t" is shown
> as "\\t" and consists of two characters, REVERSE SOLIDUS and LATIN
> SMALL LETTER T. That might be why you think there's confusing stuff
> happening :)

Oh, and the other trap you can fall into is the reverse of that:

>>> "worl\d"
'worl\\d'

This one actually triggers a warning in sufficiently-recent Pythons:

$ python3 -Wall
Python 3.7.0a0 (default:cebc9c7ad195, Jan 24 2017, 06:55:19)
[GCC 6.2.0 20161027] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> "worl\d"
<stdin>:1: DeprecationWarning: invalid escape sequence \d
'worl\\d'

A future Python may define \d to mean something else, or may trigger
an error on this.

ChrisA