Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!rutgers!mailrus!uflorida!gatech!hubcap!Kevin
From: mcvax!sys.uea.ac.uk!kh@uunet.UU.NET (Kevin Hammond CMP)
Newsgroups: comp.parallel
Subject: Re: Exception Handling in Dataflow Languages?
Message-ID: <3934@hubcap.UUCP>
Date: 19 Dec 88 13:18:37 GMT
Sender: fpst@hubcap.UUCP
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Approved: parallel@hubcap.clemson.edu

There's a paper in TOPLAS describing the exception-handling  mechanism
in VAL.  SISAL  seems to have  a  similar  mechanism,  but  these seem
rather ad-hoc.  HOPE+ and PSML (my dialect  of Standard  ML) both have
exception-handling mechanisms based on  error values.  I have  a paper
which I can distribute (or you can get  it from  UEA) which  describes
various  exception-handling techniques   (dataflow,   functional, term
rewriting), and introduces a deterministic parallel  approach based on
error values.  You have to be careful to define exactly what  you mean
by exception handling, though, event handling is not the same as error
handling. There's  a   lot of confusion between  these  which leads to
complex and over-general  mechanisms, someone (A.   Black) even argues
that you should exclude  exception  handling from  languages  entirely
just because the mechanisms can be misapplied!

A few basic references (I have more if anyone's interested):

Wetherell, C.S., "Error Data Values in the dataflow language VAL",
ACM TOPLAS, Vol. 4, No. 2, pp. 226-238, 1982.

Hammond, K., "Error Handling in the Parallel Implementation of a Lazy
Functional Language", UEA Internal Report, School of Information Systems,
University of East Anglia, Norwich, UK, 1988.
Submitted to International Journal of Parallel Processing.

Black, A., "Exception Handling: the Case Against", D.Phil thesis,
Oxford University, 1980.

Bretz, M, and Ebert, J., "An Exception-Handling Construct for
Functional Languages", in Proc. ESOP 88, Nancy, France, L.N.C.S. 300,
Springer-Verlag, 1988.


Hope this helps,
Kevin.
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