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From: Philipp Stephani <p.stephani2@gmail.com>
To: Ergus <spacibba@aol.com>
Cc: help-gnu-emacs <help-gnu-emacs@gnu.org>
Subject: Re: package-installed-p issue.
Date: Sat, 9 Jan 2021 19:02:56 +0100	[thread overview]
Message-ID: <CAArVCkQjYCXEfNCOLyUAMyooNHfneQzZafwHxTdD+ZQj6eXqeg@mail.gmail.com> (raw)
In-Reply-To: <20210109024756.en34g7b7ol45qtqs@Ergus>

Am Sa., 9. Jan. 2021 um 03:48 Uhr schrieb Ergus <spacibba@aol.com>:
>
> Hi I'm trying to simplify some of my code in the init file and
> something like:
>
> (package-installed-p 'use-package)
>
> Triggers an error so I need to do something like:
>
> (unless (fboundp 'package-installed-p)
>      (require 'package))
>
> (unless (package-installed-p 'use-package)
>    ...
> )
>
> My question is: Shouldn't package-installed-p be an autoload?
>
> Is there a reason why it is not an autoload?
>

Most functions should not be autoloaded. Autoloads are useful for
high-level interactive commands in optional libraries, so that e.g.
users can start ERT with `M-x ert' without having to load `ert'
explicitly. In code (including ~/.emacs), just use `require' to load
the required library. There's no need to surround it with `unless' -
`require' is idempotent.



      parent reply	other threads:[~2021-01-09 18:02 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20210109024756.en34g7b7ol45qtqs.ref@Ergus>
2021-01-09  2:47 ` package-installed-p issue Ergus
2021-01-09 16:53   ` Stefan Monnier
2021-01-09 18:02   ` Philipp Stephani [this message]

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