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Stan Warford wrote:
> (f: Frame) MarkRect (l, t, r, b, s: INTEGER; mode: MarkMode; show:
> BOOLEAN), NEW;
>
> ...The parameter list of MarkRect is _not_ self-documenting. All you know
> by looking at formal parameter mode is that it is an integer....
>
> It was a source
> of irritation to see an integer parameter in a formal parameter list and
> not
> know immediately which set of integer constants applied to it. I think one
> reason it has been a hard sell to the folks at Oberon microsystems is that
> they are so familiar with the framework that they forget what it is like
> for
> a novice to be learning BB for the first time.
I think Stan has identified the problem exactly, except that it is not limited to novices. Indeed, almost nothing in the parameters list is self-documenting. And typically, there are rarely enough comments. That's a major problem with modern software--it's too darned time-consuming to read, and too darned hard to learn.
Most of the target audience for any programming language or environment is people whose job only peripherally involves programming. If you appeal only to specialists, you won't even appeal to the great majority of programmers. It's impossible to make code too easy to read.
>As I understand it, 90% of the
> difficulty of implementing enumerated types is the type checking that must
> occur across modules.
According to Wirth's paper "From Modula to Oberon", the problem is that enumerated types are difficult to extend across modules. He also opposed proliferation of types. In typical Wirth fasion, rather than implement enumerated types perfectly, he simply discarded the feature.
Stan's proposed named integers _is_ simple and extensible, and could encourage improvement in readability of code. It loses clarity if you extend it, but after all, what are comments for?
Sincerely,
Rex Couture, Ph. D.
Dept. of Earth and Planetary Sciences
Campus Box 1169
Washington University in St. Louis
1 Brookings Dr.
St. Louis MO 63130
Voice: (314) 935-4194
Fax: (314) 935-7361
rex{([at]})nowhere.xy
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Received on Mon Dec 06 2004 - 23:32:19 UTC