bug#51968: Missing dependency for Xournal++

[Maxime Devos]

Hi,

Alexander Asteroth schreef op di 21-12-2021 om 09:45 [+0100]:
> [...]
> In the meantime I found that as well. But the documentation (from my
> perspective) is unfortunately incomplete. It neither specifies the
> full
> semantics (without looking into the macro-code)

‘Modify the given package inputs, as returned by package-inputs & co.,
according to the given clauses. The example below removes the GMP and
ACL inputs of Coreutils and _adds libcap to the back of the input
list_:

(modify-inputs (package-inputs coreutils)
  (delete "gmp" "acl")
  (append libcap))’

(Emphasis mine.) Seems like the behaviour of 'append' is specified?
Except that it isn't explicitely stated there can be multiple
arguments, although this seems implied by the 'delete' example.

>  nor does it tell me,
> what kind of clauses I can put e.g. into (modify-input ...).

The manual documnets ‘delete’, ’append’ and ‘replace’, and ends with
‘the last type of clause is prepend’, no?

>  How is
> (append ...) translated? The web document links to the list append
> function which it might somehow translate to but that is not
> documented
> either (at least I dont find it).

The ‘append’ procedure is from Guile, not Guix.
Also, it doesn't link to the 'append' procedure?
--- nevermind, the 'append' in the code example does link to the Guile
manual. Seems like a bug, because 'append' accepts lists, not elements
of lists. Likewise for 'delete'.

About how ‘(append ...)’ is translated:

‘The example below [...] adds libcap to the back of the input list’.

I don't see how the documentation could be more complete,
unless you're looking for a less informal description of the syntax,
e.g. as in the documentation for 'match' or 'define-record-type' in
Guile.

Greetings,
Maxime

>
https://guix.gnu.org/manual/devel/en/html_node/Defining-Package-Variants.html#index-modify_002dinputs