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RE: Proposal for study: Add a categorical Initial type to ocaml
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Date: 1999-10-14 (13:00)
From: Manuel Fahndrich <maf@m...>
Subject: RE: Proposal for study: Add a categorical Initial type to ocaml

skaller wrote:


	> Like I've been saying, with option you can turn it off, with
Obj.magic, the
	> implementor ought to be damned sure he's doing things right.  But
	> these special "uninitialized value" sorts of things, people like
	> who've gotten used to good type systems keep looking over their
	> shoulders because they're afraid it might turn around and bite
them in
	> the butt.

		How is this different from Obj.magic? Can't that bite you
	in the ass too?

The difference is that in the first case of uninitialized values, they can
crop up anywhere in your program, since they get propagated. Using Obj.magic
within a special module such as resizable arrays confines the danger to that
module. The programmer can make sure (through extensive code reviews of a
finite piece of code) that outside the module, things cannot go awry.