From: "Mark J. Reed" <markjreed@...>
Date: 2004-01-02T14:06:45+09:00
Subject: Re: Loop/Iterator questions

On Thu, Jan 01, 2004 at 08:55:54PM -0800, GGarramuno wrote:
> 1) Is there anything like Perl's continue block available?  

Not that I'm aware of, although I could easily be mistaken. 
But Ruby's looping primitives are in general rather, well,
primitive, since most of the time an iterator method is used
instead. 

> 2) Is there anything like labels for iterators or loops?  This allows
> you to do next, last, etc. on outside loops, like:
> 
>          loop1:   while x > 1
>                        while y > 1
>                            if t2 then next loop1
>                        end
>                   end
> 
> This could be emulated with a flag and an ugly if check, but I hope
> not.

That sort of nonlocal control flow is done with catch/throw in Ruby.

        catch(:done)  do
            while x > 1
                while y > 1
                    if t2 then throw :done
                end
            end
        end

Catch and throw are explicitly designed for this sort of thing, unlike
raise/rescue which are for genuine error conditions.

-Mark