This is the most intuitive thing I could come up with: since the
problem is mainly due to the order in which we try declaring the
aliases, then it suffices to simply try as much as we can, and retry
on failure until there's no more failure.
Note that it's important to detect cycles if we do such thing (which
we can by noticing that a given iteration didn't make any progress).
It works pretty well in the end and even allow us to define a new kind
of type error should there be a cyclic definition.
Tests are basically functions for which the return type should unify with bool. In principle, the type checker could also check that a test function has no arguments but, a test function with arguments wouldn't parse in the first place; feels a bit hacky but it works when considering the pipeline as a whole.
Note that the code generation is still to be done.
KtorZ