File write, weird behaviour

[Chris Angelico]

On Mon, 20 Feb 2023 at 06:24, Thomas Passin <list1 at tompassin.net> wrote:
>
> On 2/19/2023 1:53 PM, Chris Angelico wrote:
> > On Mon, 20 Feb 2023 at 03:41, Azizbek Khamdamov
> > <azizbek.khamdamov at gmail.com> wrote:
> >>
> >> Example 1 (works as expected)
> >>
> >> file = open("D:\Programming\Python\working_with_files\cities.txt",
> >> 'r+') ## contains list cities
> >
> > Side note: You happened to get lucky with P, w, and c, but for the
> > future, I recommend using forward slashes for your paths:
> >
> > open("D:/Programming/Python/working_with_files/cities.txt", "r+")
> >
> > Otherwise, you may run into annoying and hard-to-solve problems. Or
> > alternatively, you'll upgrade to a newer Python and start getting
> > warnings, which would at least tell you that there's a problem.
>
> Or use r'...' strings.  If you are copying a path to clipboard from
> Windows Explorer - a fairly common operation - it's much easier to
> prepend the "r" than to change all the backslashes to forward slashes.
>

Yep, either way. I personally prefer using forward slashes since
there's no way to end an r-string with a single backslash, which is
often useful when building a path:

# won't work
path = r"c:\path\to\some\"
open(path + "file")

# will work
path = "c:/path/to/some/"
open(path + "file")

ChrisA