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From: Gary_Wong@kcbbs.gen.nz (Gary Wong)
Newsgroups: comp.lang.pascal
Subject: Re: Gotos are ok (Was Re: IMPLEMENT GOT
Message-ID: <1991Jan24.112445.3829@kcbbs>
Date: 24 Jan 91 11:24:45 GMT
Lines: 46
Organisation: Kappa Crucis Unix BBS, Auckland, New Zealand

>I can foresee three objections to this code. Let me take them in
>order.

Okay, I will discuss how I feel with your three objections too:
>1) That code isn't efficient.
>   If the program isn't fast enough, find a better algorithm. If
>   you can't do that, recode the 1% to 10% of the program where
>   speed is critical in assembler. But don't use "efficiency" as
>an
>   excuse to put in a goto.

I see your point about not using gotos, and I agree that in 90% at least 
of cases where a goto could be used, it is not the best choice.  But 
rewriting a section of code in assembler to avoid a goto?  Once your 
in assembler, make sure it runs only on a 986 processor which eliminates 
all JMP instructions and replaces them with FOR, RPT?? I would much 
rather keep it in pascal (unless its *really* speed critical) and by 
writing it in assembler you have the problem with it bombing once in 
a thousand times you mentioned earlier.  
>2) It uses an extra variable.
Well, it doesnt sound like much, but when I come across this situation 
I'm always annoyed.  I realise that I'm worrying too much but I consider 
the extra space it takes up in the declartion, (even in the exe!!) and 
I end up using 1 variable to do 2 different things which I know I shouldnt 
do but i do anyway.  But you have to declare a label to use a goto so 
i guess the variable doesnt make a lot of difference.
>3) It isn't really clear.
Now this is what I disagree with you about.  People have mentioned that 
gotos make code unclear, so why bother using another solution that makes 
code unclear?  I agree that a goto is not a nice solution to this problem, 
but yours is not perfect either.

Although I have argued about your examples for {not using gotos, I should 
say that I have come across almost exactly the same situation, many 
times.  And I havent used a goto yet.  Also, when writing Pascal I like 
to know exactly what the code will compile to.  By using a goto Im always 
afraid (I have no idea how valid this is) that Im going to jump over 
an important section of code like a PUSH or POP - at best, you lose 
a word of stack space, at worst, the entire stack dies - and that the 
best solution would be for the compiler to implement a 'Local exit' 
command (i remember 'exit for' from when i programmed in basic a while 
back, cant remember exactly how it works) and I think that would be 
the most elegant solution.  Between structured constructs (repeat etc), 
exit's, and local exits, theres not many cases where a goto would be 
needed at all.
Gary.