[ruby-talk:4739] Re: Possible regex bug?

Of course!

Thanks again, Dave... as you say on your web page, 
"Select isn't broken..."  ;)

See below.

> 
> Always be careful with patterns containing '*'. For example,
> 
>    'caaaaaat'  =~ /a*/    # => 0
>    p $&                   # => ""
> 
> /a*/ matched the string by matching exactly _zero_ 'a's at the start.
> 
> > But: p "4.2, 3.1, 5.3".split(/,? */)
> 
> Your pattern also matches a zero length string: 'no commas and no
> spaces'. This is why split isn't doing what you want.

Yes, right.

> However, in your problem definition, you said you wanted an optional
> comma followed by _one_ or more spaces. That's a different beast:

Well, I really meant 0 or more. Probably. :)

>    "4.2, 3.1, 5.3".split(/,? +/) # => ["4.2", "3.1", "5.3"]
> 
>                              ^
>      one or more... ---------+
> 
> You could also have used scan:
> 
>    "4.2, 3.1, 5.3".scan(/[\d.]+/) # => ["4.2", "3.1", "5.3"]
>