Re: GHC/Hugs Status (was Re: simple interface to web?)

[Fergus Henderson]

On 15-Jul-1998, S. Alexander Jacobson <[EMAIL PROTECTED]> wrote:
> On Tue, 14 Jul 1998, Alastair Reid wrote:
> > and it's not clear that
> > fetching URLs outside the IO monad is sensible.  Not at all clear.
> 
> I am thinking about using Haskell for XML scripting in which one imports
> XML DTD's into Haskell as a set of data statements and then reads XML
> datastructures off of web pages out on the net.  This should be legal
> outside the IO monad as long as the page being accessed does not expire
> before the computation is complete.  I think failure of retrieval is an
> issue of operational semantics rather than denotational semantics.  
> I figure that the reliability of the network should be treated like
> the reliability of the underlying computer (which can run out of memory).

Well, if you're willing to ignore the possibility that the page will change,
you should be willing to ignore the possibility that accessing the page
may fail... or at least put off dealing with such failures until
Haskell has better exception support.  So I don't think it should affect
your interface.

But I think it would be better for the interface to use the IO Monad anyway.

-- 
Fergus Henderson <[EMAIL PROTECTED]>  |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>  |  of excellence is a lethal habit"
PGP: finger [EMAIL PROTECTED]        |     -- the last words of T. S. Garp.