[Caml-list] exhaustiveness checking within a submatch

[Martin DeMello <martindemello@gmail.com>]

Just curious as to why the compiler can't handle this, since in theory
everything is statically deducible:

# type test = A | B | C | D;;
type test = A | B | C | D

# let f = A;;
val f : test = A

# match f with A -> 1 | B -> 2 | C | D -> ( match f with C -> 3 | D -> 4);;
Characters 40-71:
                                                               Warning
8: this pattern-matching is not exhaustive.
                                                       Here is an
example of a value that is not matched:
(A|B)
Characters 40-71:
Warning 8: this pattern-matching is not exhaustive.
Here is an example of a value that is not matched:
(A|B)
- : int = 1

martin