From: Stephen Berman <stephen.berman@gmx.net>
To: Hongyi Zhao <hongyi.zhao@gmail.com>
Cc: help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Re: let*: Wrong type argument: stringp, nil
Date: Sat, 25 Sep 2021 16:45:48 +0200 [thread overview]
Message-ID: <87a6k0sogz.fsf@gmx.net> (raw)
In-Reply-To: <CAGP6PO+BpmHC1_JVqXdiMaA__OckpE87b4_uF=Rg-1wAadtcgg@mail.gmail.com> (Hongyi Zhao's message of "Sat, 25 Sep 2021 21:49:38 +0800")
On Sat, 25 Sep 2021 21:49:38 +0800 Hongyi Zhao <hongyi.zhao@gmail.com> wrote:
[...]
> But the actual demand exceeds the simple processing above, I mean, the
> real project maybe located under a specific folder with multiple level
> subdirectories. In this case, when I open a python file, the function
> should do the following: Search the current directory and its parent
> directories at all levels in turn. Once the ".python-version" file is
> found, activate the corresponding environment and exit the cycle;
> Otherwise, continue to search upwards until the certain top level
> directory, say, $HOME. Based on the above requirements and the code
> snippets given here [1-2], I finally figured out the following
> solution:
>
> -------
> (defun parent-directory (dir)
> (unless (equal (getenv "HOME") dir)
> ;file-truename or directory-file-name
> (file-name-directory (directory-file-name dir))))
>
>
> (defun find-file-in-heirarchy (current-dir fname)
> "Search for a file named FNAME upwards through the directory
> hierarchy, starting from CURRENT-DIR"
> (let ((file (concat current-dir fname))
> (parent (parent-directory (expand-file-name current-dir))))
> (if (file-exists-p file)
> file
> (when parent
> (find-file-in-heirarchy parent fname)))))
>
>
> (defun try/pyvenv-workon ()
> (when (buffer-file-name)
> (let ((file (find-file-in-heirarchy (buffer-file-name)
> ".python-version")))
> (when (file-exists-p file)
> (pyvenv-workon (with-temp-buffer
> (insert-file-contents file)
> (nth 0 (split-string
> (buffer-string)))))))))
>
> (add-hook 'python-mode-hook 'try/pyvenv-workon)
> -------
>
> It works like a charm. But any suggestions/enhancements/comments will
> be greatly appreciated.
>
> [1] https://stackoverflow.com/a/14096693 (*)
> [2] http://sodaware.sdf.org/notes/emacs-lisp-find-file-upwards/
>
> * Indicated that this is my main reference source code.
Doesn't using the built-in Emacs function `locate-dominating-file', as
mentioned in the stackoverflow thread, work just as well as
`find-file-in-heirarchy'?
Steve Berman
next prev parent reply other threads:[~2021-09-25 14:45 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-24 14:52 let*: Wrong type argument: stringp, nil Hongyi Zhao
2021-09-24 14:57 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-25 1:29 ` Hongyi Zhao
2021-09-25 23:42 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-25 10:09 ` Stephen Berman
2021-09-25 10:45 ` Hongyi Zhao
2021-09-25 11:04 ` Stephen Berman
2021-09-25 13:49 ` Hongyi Zhao
2021-09-25 14:45 ` Stephen Berman [this message]
2021-09-25 15:03 ` Hongyi Zhao
2021-09-28 3:08 ` Hongyi Zhao
2021-09-28 3:21 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-28 3:24 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-28 5:25 ` Hongyi Zhao
2021-09-28 7:20 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-28 8:02 ` Yuri Khan
2021-09-28 8:24 ` Hongyi Zhao
2021-09-29 1:43 ` Hongyi Zhao
2021-09-29 2:03 ` Hongyi Zhao
2021-09-29 3:02 ` Hongyi Zhao
2021-09-29 3:57 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-29 6:15 ` Hongyi Zhao
2021-09-29 6:29 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-29 7:37 ` Hongyi Zhao
2021-09-29 8:21 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-29 9:02 ` Hongyi Zhao
2021-09-29 9:14 ` Yuri Khan
2021-09-29 10:29 ` Hongyi Zhao
2021-09-29 12:29 ` Yuri Khan
2021-09-29 12:49 ` Hongyi Zhao
2021-10-08 3:36 ` Hongyi Zhao
2021-10-10 14:05 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-30 3:38 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-29 4:35 ` Emanuel Berg via Users list for the GNU Emacs text editor
2021-09-29 6:17 ` Hongyi Zhao
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