NixCon 2022

Nix error traces improvements #6204
2022-10-20 , Main track (Gym)

Based on simple examples, this will showcase error reporting improvements implemented in the open https://github.com/NixOS/nix/pull/6204 PR.


For some errors, nix reports an odd, seemingly unrelated position. Or no position at all.
Usually, the same location is used for several potential errors inside a given scope. This PR makes the relation between the error and the location more explicit. For example using "in the second argument of the function call" when the only available location is the function call itself. In some occasion, it adds error messages with no location, and an intermediate "context" trace for the closest known location.


Do you allow your talk to be recorded? – yes What level of experience in Nix is the talk addressed to?

Beginner

Guillaume uses nix a lot, and sometimes inadvertently dives into its source code.

He has a background in computer science, engineering and applied mathematics. He is passionate about understanding complex systems and untangling intricate issues.