[Nix-dev] Multiple outputs: is a first output necessary?

[Ludovic Courtès]

Hi!

Freddy Rietdijk <freddyrietdijk at fridh.nl> skribis:

> I'm using Nix and now also multiple outputs for my data analysis and
> simulations. Many scripts generate several files and instead of having them
> together in the same store path I would prefer to put them in separate
> store paths.
>
> I'm not using any of the common outputs like $out and $bin. The multiple
> outputs feature seems to require that $out is used. Therefore I now just
> put a single file in $out. What is the reason this is needed? I saw in the
> documentation that leftover files are typically put in $out.

Internally the “out” output is not required at all, except for
fixed-output derivations.

The only difference compared to other output names is that it gets
special treatment when computing its store file name (see
‘makeOutputPath’ in store-api.cc.)

Ludo’.