Re: Implementing Nix's command-not-found in Guix

[indieterminacy <indieterminacy@libre.brussels>]

On 04-03-2023 22:42, Sarthak Shah wrote:
> Hello Guix!
> 
> I'd like to implement something similar to NixOS's command-not-found
> in Guix.
> As you can see in the repository below, it contains a nix file which
> is essentially a shell script which runs the second file, a perl
> script, if the user enters a command which is not found on this
> system. The perl script suggests names of packages containing said
> command which it pulls from an SQL database.
> https://github.com/NixOS/nixpkgs/tree/master/nixos/modules/programs/command-not-found
> This would make Guix much more user-friendly; for example, new Guix
> System users often struggle to figure out how to add the "clear"
> command to their shell. command-not-found would immediately inform
> them that it can be found in the ncurses package.
> 
> How would you recommend I go about implementing something similar for
> Guix?
> I have unfortunately been unable to find a database or anything
> similar listing files outputted to /bin by each package, which would
> in my opinion be the starting step.
> 

While you wait for a better answer it may be worth trying out IDUtils 
(which if I recall Ludo recommended during a Guix blogpost).
```
  An ID database is a binary file containing a list of file names, a list 
of tokens, and a sparse matrix indicating which tokens appear in which 
files.

With this database and some tools to query it (described in this 
manual), many text-searching tasks become simpler and faster. For 
example, you can list all files that reference a particular #include 
file throughout a huge source hierarchy, search for all the memos 
containing references to a project, or automatically invoke an editor on 
all files containing references to some function or variable. Anyone 
with a large software project to maintain, or a large set of text files 
to organize, can benefit from the ID utilities.
```
https://www.gnu.org/software/idutils/manual/idutils.html

As such, even if it is not a complete solution it could allow you to 
identify or exclude things in advance of a more complete or bespoke 
solutions.

Happy hacking!

-- 
Jonathan McHugh
indieterminacy@libre.brussels