Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!usc!apple!motcsd!xdos!doug
From: doug@xdos.UUCP (Doug Merritt)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Fonts and freeing memory
Message-ID: <626@xdos.UUCP>
Date: 21 Jan 90 16:56:38 GMT
References: <1990Jan17.013417.20587@haven.umd.edu> <9001182253.AA18421@en.ecn.purdue.edu>
Reply-To: doug@xdos.UUCP (Doug Merritt)
Organization: Hunter Systems, Mountain View CA (Silicon Valley)
Lines: 37

In article <9001182253.AA18421@en.ecn.purdue.edu> bevis@EE.ECN.PURDUE.EDU (Jeff Bevis) writes:
>
>I have obviously been using memory-destructive drugs.  Indeed I was wrong...
>and I apologize for spreading bogus myth.... I would rather change my previous
>statement to the form of "using two if's instead of the && would be clearer
>and less confusing" instead of what I did state.

I don't mean this to be a flame, but that's not true either. This construct
is called "short circuit evaluation", and is as much a hallmark of C
as are, say, increment operators like "++i". It is *not* considered unclear
to take advantage of this feature. Quite the opposite.

It's true that features of a language which are not universally used in other
languages can be confusing to new users of that language. But that doesn't
mean they should be avoided. One should, in general, write code that assumes
general fluency on the part of the reader, rather than trying to write code
which assumes that the reader is a novice in the language. Doing so would
mean wholly avoiding such language features, implying that there is something
wrong with using them. There is not.

As a matter of fact, this is an area in which C has been rather influential.
As with the "++" operator, the short circuit evaluation feature has been
adopted more and more widely in new languages. This is simply to stress
that it *is* a feature.

As with any design, one should not confuse novice usability (learning curve
issues) with expert usability. By analogy, the Amiga's multitasking features
have been confusing to learn to work with for programmers accustomed to
non-multitasking systems like the IBM PC and the C64, etc, but that
doesn't make those features bad. They were not confusing to programmers who
were already accustomed to multitasking environments, particularly those who
were used to message passing as well. It's just a question of which metaphors
one has previous familiarity with.
	Doug
-- 
Doug Merritt		{pyramid,apple}!xdos!doug
Member, Crusaders for a Better Tomorrow		Professional Wildeyed Visionary