Re: let*: Wrong type argument: stringp, nil

[Yuri Khan]

On Tue, 28 Sept 2021 at 10:08, Hongyi Zhao <hongyi.zhao@gmail.com> wrote:

> Now I'm trying another test code snippet based on the idea posted here [1]:
>
>     (while (not (file-exists-p ".python-version"))
>           (cd "..")
>     ))
>
> But when I test the above code in scratch buffer, it seems to be stuck
> in an endless loop and running there all the time. Any hints for this
> problem?

You’re not handling the case here that you reached the root directory
without finding a .python-version file.

You will really get better results if you use locate-dominating-file.
If you’re trying to learn, learn by reading that function. As a bonus,
it does not mess with the buffer’s default directory.