error:
       … while evaluating the condition of the assertion '((x: x) == (x: x))'
         at /pwd/lang/eval-fail-assert-equal-function-direct.nix:3:1:
            2| # This only compares a direct comparison and makes no claims about functions in nested structures.
            3| assert
             | ^
            4|   (x: x)

       error: distinct functions and immediate comparisons of identical functions compare as unequal