From: Emanuel Berg via Users list for the GNU Emacs text editor <help-gnu-emacs@gnu.org>
To: help-gnu-emacs@gnu.org
Subject: Re: let*: Wrong type argument: stringp, nil
Date: Wed, 29 Sep 2021 06:35:33 +0200 [thread overview]
Message-ID: <878rzgq9re.fsf@zoho.eu> (raw)
In-Reply-To: CAGP6POJOaRjxbyq9x0L2xnLo8=AnWgUAoY2TpFY3zb5rNQ8iqg@mail.gmail.com
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 ...
--
underground experts united
https://dataswamp.org/~incal
next prev parent reply other threads:[~2021-09-29 4:35 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 [this message]
2021-09-29 6:17 ` Hongyi Zhao
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