Path: utzoo!attcan!uunet!mcvax!enea!sommar
From: sommar@enea.se (Erland Sommarskog)
Newsgroups: comp.lang.misc
Subject: Re: What makes a language "easy" to program in?
Message-ID: <3496@enea.se>
Date: 13 Jun 88 21:47:30 GMT
Organization: ENEA DATA AB, Sweden
Lines: 40

Richard Harter (g-rh@CCA.CCA.COM.UUCP) writes:
>	As a side point, this examples illustrates a comon deficiency
>in programming languages -- they force the user to specify too much.
>What is wanted in this case is really something like
>	for i in {0,...,n-1} a[i] = 0;
>or
>	for all i in range of a, a[i] = 0;
>or even
>	a = 0;
>	The point is that the quoted forms specify too much, and too
>little.  They specify too much in that they specify the details of the
>calculation, and too little in that the desired result is not explicit,

Spot on it! This concrete example gets better in Ada:
       FOR i IN a'range LOOP a(i) := 0; END LOOP;
Or better:
       a := (OTHERS => 0);
The ultimate winner is VAX-Pascal, though:
       a := zero;
The predefined function zero can be used to clear any array or record. 
  It should be added that although Ada helps you in many cases, it is 
too verbose for the purposes desired here. (VAX-Pascal, monster of  
Pascal as it may be, is insufficient in many other occassions.)

>The best programming language only has one instruction:
>
>	"Do what I want"

Here's the pseudo-code for that compiler:
   Read(Line);
   Trim_and_compress(Line);
   IF Line = "Do what I want" THEN
      Write("But what do you want?");
   ELSE
      Write("Syntax error");

-- 
Erland Sommarskog           
ENEA Data, Stockholm        
sommar@enea.UUCP            
Mail your NO votes for rec.music.rock to: jfc%Athena.mit.edu@mit-eddie.UUCP