From: Stefano Crocco <stefano.crocco@...>
Date: 2008-03-03T23:57:36+09:00
Subject: Re: Normal For Loop

Alle Monday 03 March 2008, jwmerrill@gmail.com ha scritto:
> On Mar 3, 9:37 am, Cory Cory <cg821...@ohio.edu> wrote:
> > I tried to do this the other night, but right now I can't find a good
> > example so here it goes:
> >
> > a = some_array
> > minValue = 999999
> > for(i=0; i<a.length && minValue!=0; i+=1) {
> >    minValue = (5000 - a[i]).abs
> >
> > }
>
> What does this example do exactly?  It seems to run until it finds a
> value in a that is equal to 5000, and then stop without reporting
> anything.
>
> a.detect {|n| 5000 == n}
>
> or
>
> a.any? {|n| 5000 == n}
>
> See, this is actually more concise and readable, I think.
>
> > This isn't the best example.  However, there are many times like the
> > loop above where I want to go through the whole thing, but if I find
> > exactly what I am looking for, I want to bail out early instead of
> > wasting that processing time.
> >
> > Also, I sometimes may want to not actually iterate straight through, but
> > browse through the array in some more complex order.
>
> The point is not that no examples exist, but that they realistically
> don't come up very much.  Get familiar with the methods in Enumerable,
> Array, and Numeric.  Each time you want to write a for loop, try and
> use one of those instead, and if you get stuck, ask for advice.
> You're solution will almost always be more readable, and maybe 1 time
> in 100 you'll need to use a while loop.
>
> JM

If you want to exit the loop before all iterations are done, you can use
break.

Stefano