document ```Alternatively `nix run` the .lock attribute of your package.```

[lizelive]

using the ml example

following the bash command works, but im interested in how to

nix run the .lock attribute of your package.

[lizelive@reese:/tmp/experment.a9d]$ nix run --impure #someproject.lock
warning: Git tree '/tmp/experment.a9d' is dirty
error:
       … while calling the 'head' builtin

         at /nix/store/g68f5abh3xhcz8xsdlfw7wkgkkcx3nwy-source/lib/attrsets.nix:820:11:

          819|         || pred here (elemAt values 1) (head values) then
          820|           head values
             |           ^
          821|         else

       … while evaluating the attribute 'value'

         at /nix/store/g68f5abh3xhcz8xsdlfw7wkgkkcx3nwy-source/lib/modules.nix:807:9:

          806|     in warnDeprecation opt //
          807|       { value = builtins.addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          808|         inherit (res.defsFinal') highestPrio;

       (stack trace truncated; use '--show-trace' to show the full trace)

       error: The lock file ./lock.json
         for drv-parts module 'someproject' is missing.

       To create or update the lock file, run:

         bash -c $(nix-build /nix/store/9g39yk3ic1iqgn8b34cqsyn0g5gfvcw6-refresh.drv --no-link)/bin/refresh

       Alternatively `nix run` the .lock attribute of your package.

[phaer]

nix run --impure #someproject.lock

Ah, that's confusing. The packages name is "someproject", but if you take a look at nix flake show you'll see that the attribute is named 'default', so

nix run .#default.lock

should work (and does on my machine). No need to use --impure as nix run commands are impure anyways.

[DavHau]

We could add an option 'paths.flakeAttrPath' which, when set, would improve the error message to be more specific.

[phaer]

I think in this specific case it might suffice to rename the packages attribute from default to "myproject" which could arguably be less confusing. What would you think of that?

[DavHau]

Hm, that would imply modifying the flake. Currently all the single-package examples share the exact same flake.nix and I like to keep it that way to simplify maintenance.

Maybe the confusing part is that the lock update script is not a separate flake output itself that can be discovered by nix flake show. We could add an app to all the flakes, which iterates over all packages and updates them. Or a dream2nix devShell wirh a cmdline tool that is capable of doing that