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From: liam@cs.qmw.ac.uk (William Roberts)
Newsgroups: comp.compilers
Subject: Re: Semicolons (Re: Low-Rent Syntax)
Keywords: parse, design
Message-ID: <2753@sequent.cs.qmw.ac.uk>
Date: 3 Sep 90 17:42:01 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: liam@cs.qmw.ac.uk (William Roberts)
Organization: Computer Science Dept, QMW, University of London, UK.
Lines: 26
Approved: compilers@esegue.segue.boston.ma.us

In <1990Aug29.140407.28378@maths.nott.ac.uk> anw@maths.nott.ac.uk (Dr A. N. Walker) writes:

>       while (x)
>               skip;           /* Down with empty null statements! */

The thing I hate most about Modula-2 is that it won't allow a semicolon on
the last statement of a loop-body, on the dubious grounds that you don't need
one. Languages which do that clearly aren't written to be edited: at least,
not without clever editors that won't let you forget the very necessary
semicolon between the old last-statement-of-the-loop and the new one you have
just inserted.

Language designers should try to remember that a) programs get modified, and
b) the syntax of the language is in part its "user interface" and should be
given some thought as to its usability, not just its denotational purity!
-- 
William Roberts                 ARPA: liam@cs.qmw.ac.uk
Queen Mary & Westfield College  UUCP: liam@qmw-cs.UUCP
Mile End Road                   AppleLink: UK0087
LONDON, E1 4NS, UK              Tel:  071-975 5250 (Fax: 081-980 6533)
[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]
-- 
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