> And why not "as", i.e. "t as x", as I explained once in a previous post.
> I never did get an explanation as to why this wasn't an better solution.  It
> reuses a rarely-used keyword in a perfectly backward-compatible way.  

This is not backward-compatible since ident1 as ident2 is a special
case of pattern as ident. Hence ident1 as ident2 already has a
meaning in Caml: it means that you want to write ident2 as an alias
for ident1.

Best regards,

-- 
Pierre Weis

INRIA, Projet Cristal, http://pauillac.inria.fr/~weis