[fpc-pascal] Legitimate use of for and break

[Santi]

El 16/06/2023 a las 16:09, Mattias Gaertner via fpc-pascal escribió:
> On Fri, 16 Jun 2023 20:51:42 +0700
> Hairy Pixels via fpc-pascal <fpc-pascal at lists.freepascal.org> wrote:
>
>>> On Jun 16, 2023, at 6:23 PM, Thomas Kurz via fpc-pascal
>>> <fpc-pascal at lists.freepascal.org> wrote:
>>>
>>> Whether it's elegant is a different question. In my opinion YES
>>> because it often gives better readable code than nested "if"
>>> statements inside the loop. But I've also read that using "break"
>>> is discouraged because it shows a bad choice of the loop range.
>> This is highly suspect. Doing an early break in loops is the essence
>> of how to do linear searching. No idea who thinks that's a bad idea.
> 20 years ago there were some programmers, claiming a loop condition
> must only be at start or end, but not in the middle.
I mostly agree with that programmers. That's called structured 
programming.  "Break" and "continue" are in fact, a subset of GOTO

When you see a structure, a block, you know at the beginning (or end of 
the block) the exit conditions. So you can skip the block and you know 
the conditions after the block. It is very useful when you are skimming 
the code or debugging. You don't have the investigate the inner loop to 
see if there are hidden GOTOs.

But, as any other golden rule, you must know when it makes sense to 
ignore it.
I use the break, but only at the beginning of the loop. (or exit in 
function/procedure)
And sometimes with deep nested loops, but, when I commit such crime, I 
highlight it with neon lights in the comments.

I really hate having the read the full code to guess whats happening. 
Structured programming  is your friend.

>
> Gladfully, most programmers came to their senses.
>
> Mattias
> _______________________________________________
> fpc-pascal maillist  -  fpc-pascal at lists.freepascal.org
> https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-pascal


-- 
Saludos
Santi