nix-super/doc/manual/rl-next/source-positions-in-errors.md
Rebecca Turner cb7fbd4d83
Print value on type error
Adds the failing value to `value is <TYPE> while a <TYPE> is expected`
error messages.
2024-01-22 08:56:02 -08:00

779 B

synopsis issues prs
Source locations are printed more consistently in errors 561 9555

Source location information is now included in error messages more consistently. Given this code:

let
  attr = {foo = "bar";};
  key = {};
in
  attr.${key}

Previously, Nix would show this unhelpful message when attempting to evaluate it:

error:
       … while evaluating an attribute name

       error: value is a set while a string was expected

Now, the error message displays where the problematic value was found:

error:
       … while evaluating an attribute name

         at bad.nix:4:11:

            3|   key = {};
            4| in attr.${key}
             |           ^
            5|

       error: expected a string but found a set