Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!mintaka!spdcc!esegue!compilers-sender
From: rob@baloo.eng.ohio-state.edu (Rob Carriere)
Newsgroups: comp.compilers
Subject: Re: Semicolons (Re: Low-Rent Syntax)
Keywords: parse, design
Message-ID: <9009052108.AA15597@baloo.eng.ohio-state.edu>
Date: 5 Sep 90 21:08:29 GMT
References: <9008202341.AA06543@llama.ingres.com> <4032@rtifs1.UUCP> <1990Aug29.140407.28378@maths.nott.ac.uk>
Sender: compilers-sender@esegue.segue.boston.ma.us
Reply-To: rob@baloo.eng.ohio-state.edu (Rob Carriere)
Organization: The Ohio State University Dept of Electrical Engineering
Lines: 41
Approved: compilers@esegue.segue.boston.ma.us
In-Reply-To: <2753@sequent.cs.qmw.ac.uk>

In article <2753@sequent.cs.qmw.ac.uk> you write:
[agreeing with liam@cs.qmw.ac.uk]
>[I have seen many reports that the semicolon as separator, as in Algol 60
>and Pascal, is much harder to get right than the semicolon as terminator,
>as in PL/I and C. -John]

The people at the math department of the Eindhoven University of Technology
claimed that this was because everybody _wrote_ semicolons as terminators.
They said that in a language with semicolon separators one should not write

S1;
S2;
S3

but

 S1
;S2
;S3

I tried this with some Algol 60 programs, and my experience is that it looks
funny for a day or so, but after that you won't have any problems with
forgotten or extra semi's (you may have other problems :-)

Comment1: Accidentely forgetting to insert a semi when you add a statement at
the _top_ is also visually obvious:

 S0
 S1
;S2
;S3

Comment2: I never bothered to find out who invented this convention, so I
can't give proper credit.

Rob Carriere, rob@kaa.eng.ohio-state.edu
"De semicolonius non est disputandum"  :-)
[Ugh.  I rest my case. - John]
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