Ludovic Courtès <ludo@gnu.org> writes:

> Hi!
>
> guix-commits@gnu.org skribis:
>
>> commit 2a7e1121d83ee173a7a0dbfb978a4ac363c7c4a6
>> Author: Mathieu Othacehe <othacehe@gnu.org>
>> AuthorDate: Wed Nov 4 14:39:40 2020 +0100
>>
>>     guix: store: Add ensure-path.
>>     
>>     * guix/store.scm (ensure-path): New procedure.
>
> [...]
>
>> +(define-operation (ensure-path (store-path path))
>> +  "Make PATH a temporary root for the duration of the current session.
>> +Return #t."
>> +  boolean)
>
> Looking at LocalStore::ensurePath, I don’t think a GC root is made.
> You have to call ‘add-temp-root’ if you want that to happen, no?
>
> However ‘ensure-path’ can substitute the store item, which I suppose
> means you can substitute .drv files without building them, am I right?
> :-)

That's an exciting prospect! That would help a lot with the Guix Build
Coordinator, being able to substitute derivations without building them.