Calling use-package multiple times on the same package

[wagk]

After some testing, I'm currently running under the assumption that yes, you can call use-package multiple times on a single package.

However, it would be nice to get some confirmation as well; Is it possible to call use-package multiple times on a single package? Are there any caveats that I should be looking out for when doing this?

[npostavs]

Are there any caveats that I should be looking out for when doing this?

The old :config block is not replaced (assuming there is deferred loading). For example,

(use-package 'foo
   :defer t
   :config (message "configuring foo"))
(use-package 'foo
   :defer t
   :config (message "configuring foo again"))
(require 'foo)

would print both configuring foo and configuring foo again. This may or may not be what you want. If you're changing a use-package form and then re-evaluating it, it's likely not what you want.

[wagk]

I'm currently in the process of migrating my configuration into an .org file, leaving behind a small .el file to bootstrap the environment needed for the rest of the configuration.

Within the bootstrap file I would like to define core features I'll need (things like a tiny evil config and a very basic helm config) while leaving the more heavyweight configurations in the org file, explaining why I would potentially want to call use-package more than once per init.

I assume the chained :config blocks are called in order when the package loads?

[npostavs]

I assume the chained :config blocks are called in order when the package loads?

Yes, I think so.

[zzamboni]

@wagk FWIW, you can also use org-mode's noweb features to bring together multiple snippets into the corresponding section of the use-package declaration. You can see what I mean in my init.org: https://github.com/zzamboni/dot-emacs/blob/master/init.org#org-mode

If you look at the raw org file, you'll see that many of the src blocks are labeled with the :noweb-ref header to indicate the section under the main use-package org statement where they need to be placed.

[dieggsy]

@zzamboni holy hell. now that's cool. Been using org for my config for a while now, hadn't seen that usage before.

[zzamboni]

Glad you found it neat! My first attempt at literate programming was in fact using noweb many years ago, so I found it nice that org-mode supports it too. I think it's nice, although I wish there were better support to indicate the block name/noweb-ref when exporting. As it stands, I think the unnamed blocks can be confusing. There was a question about this recently in the org-mode mailing list, and I learned that you can customize org-babel-exp-code-template to achieve a similar effect, but that approach doesn't work for :noweb-ref (only for #+NAME), so I'm still playing with it.

[TLATER]

Just to provide another use case; I like setting up built-in packages with use-package. When setting up gnus, I want to add another mail source on my work machine in a block somewhat like this:

(cond ((string-equal (system-name) "work")
           (progn
             (add-to-list 'gnus-secondary-select-methods '(nnimap "Work"...)))

With multiple use-package declarations I can do that without breaking the whole load timing chain :D

[mankoff]

I've run into an issue with multiple calls to use-package.

If package A is loaded multiple times, and package B has an :after A, then B may load after the first A load, even if it depends on features set in subsequent A loads. I solved this by setting an explicit and long defer option for B, but that fix has its own drawbacks.

I'm going to solve this by having only one use-package call per package, and making use of <<noweb>> blocks.

[skangas]

It seems like all questions here were resolved, so I'm closing this issue now. Please report back if I missed something.