Re: [TYPES] breaking abstraction with ML exceptions
François Pottier <[email protected]>
| Newsgroups | gmane.comp.science.types |
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| Message-ID | <[email protected]> |
[ The Types Forum, http://lists.seas.upenn.edu/mailman/listinfo/types-list ]
Hi Sam,
Le 28/03/2018 à 15:20, Sam Lindley a écrit :
> My motivation is understanding how this kind of pattern interacts with
> various designs for effect type systems that track exceptions - and
> whether one could perhaps get away with forbidding it.
In OCaml, it might seem tempting to forbid the exception-aliasing
declaration, "exception A = B". But I believe that that still would not
be sufficient
to eliminate exception aliasing, by which I mean the possibility that
a single (dynamic) exception is known under two distinct (static) names.
This is due to other language features that introduce aliasing, such
as module aliasing declarations ("module A = B") and first-class
modules (a function that expects two first-class modules as arguments
can be applied twice to the same module).
--
François Pottier
[email protected]
http://gallium.inria.fr/~fpottier/