Path: utzoo!attcan!uunet!mcvax!ukc!dcl-cs!nott-cs!anw
From: anw@nott-cs.UUCP
Newsgroups: comp.lang.misc
Subject: Re: Expression Based Language
Message-ID: <605@tuck.nott-cs.UUCP>
Date: 9 Jan 89 15:56:15 GMT
References: <3300001@uxg.cso.uiuc.edu> <3290002@hpctdls.HP.COM> <4505@xenna.Encore.COM> <2583@ficc.uu.net> <9310@ihlpb.ATT.COM> <11359@hadd
Reply-To: anw@maths.nott.ac.uk (Dr A. N. Walker)
Organization: Department of Mathematics, The University, NOTTINGHAM, NG7 2RD, UK.
Lines: 23

In article <11359@haddock.ima.isc.com> karl@haddock.ima.isc.com (Karl Heuer)
writes:
	[a thoughtful and interesting article about how to extend C into a
	 full expression language.]

>[...].  On the other hand, a language with expression/statement equivalence
>probably shouldn't be based on C in the first place, since several constructs
>become redundant (braces vs parens, semicolon vs the comma operator, if-then
>vs the ternary operator).

	On the third hand [:-),*], this redundancy can be very helpful to
humans.  Eg, if parens/braces/brackets were everywhere interchangeable, then
a measure of "elegant variation" makes multi-bracketed expressions more
readable and may help the compiler to produce better error messages (by
localising bracket mis-matches).  Similarly, having both "if-then" and "?:"
gives the human some syntactic sugar with which to clarify meaning.

-------
* On a clock, the third hand is presumably the second hand.

-- 
Andy Walker, Maths Dept., Nott'm Univ., UK.
anw@maths.nott.ac.uk