From: Hongyi Zhao <hongyi.zhao@gmail.com>
To: Emanuel Berg <moasenwood@zoho.eu>,
help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Re: let*: Wrong type argument: stringp, nil
Date: Wed, 29 Sep 2021 14:17:02 +0800 [thread overview]
Message-ID: <CAGP6POKis1pHj0H+37_XZzJkqajtKzrO3unQZCrXgsRRROE2BQ@mail.gmail.com> (raw)
In-Reply-To: <878rzgq9re.fsf@zoho.eu>
On Wed, Sep 29, 2021 at 12:35 PM Emanuel Berg via Users list for the
GNU Emacs text editor <help-gnu-emacs@gnu.org> wrote:
>
> Hongyi Zhao wrote:
>
> > (defun try/pyvenv-workon ()
> > (when (locate-dominating-file (buffer-file-name) ".python-version")
> > ;https://emacs.stackexchange.com/questions/9474/let-statement-throws-error-on-assigning-a-form-to-a-variable
> > (let ((file (concat (locate-dominating-file (buffer-file-name)
> > ".python-version") ".python-version")))
> > (pyvenv-workon (with-temp-buffer
> > (insert-file-contents file)
> > (nth 0 (split-string (buffer-string))))))))
> >
> > BTW, should I use `let' or `let*' here?
>
> `let*' always works, `let' works when there is no references
> to previous bindings in any binding...
>
> So if it works and you have let, you have done the
> right thing!
>
> In theory, because of the independence of the individual
> bindings with let, it can be used to compute in parallel - but
> I don't think that actually happens - an urban legend ...
>
> In your code you only have "file" so while both would work,
> let* is unnecessary ...
Wonderful explanation. Got it. Thank you very much again.
HZ
prev parent reply other threads:[~2021-09-29 6:17 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
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 [this message]
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