Extraction: fixed beta-red with Obj.magic (#2795 again) + other simplifications

 Unfortunately, my first attempt at replacing (Obj.magic (fun x -> u) v)
 by ((fun x -> Obj.magic u) v) was badly typed, as seen in FingerTree:
 the argument v should also be magic now, otherwise it might not have
 the same type as x.

 This optimization is now correctly done, and to mitigate the potential inflation
 of Obj.magic, I've added a few simplification rules to avoid redundant magics,
 push them down inside terms, favor the form (Obj.magic f x y z), etc.

0 files changed, 0 insertions, 0 deletions