*Disclaimer*: This is intended for discussion
My impression is that the with-exceptions backend is to be superseded by the
without-exception backend, which is more general and more efficient. Therefore,
seeing the added complexity of maintaining the two in parallel, I see no good
reason to keep the with-exceptions version now that the equivalence of their
semantics have been proved.
It will also be nice to reduce divergences between the different backends ; and
this should make further simplifications possible (e.g. some thunkings may no
longer be needed)
Of course I am ready to hear arguments in favor of keeping it, be it in the mid-
or long-term.
This patch removes the `--avoid-exceptions` flag, making it the only option, and
the corresponding `with_exceptions` variant of the dcalc->lcalc translation. It
doesn't do further simplifications.
A little bit of effort enables us to propagate valid typing annotations, making
subsequent typing re-inference easier (and avoiding a traversal just to remove
type annotations)
