I've been using these two lines to capture text that only appears once, but 
the second line bothers me a little.  Is there a one-line idiom for this 
that extracts groups like #scan but returns a string instead of an array so 
the second line isn't needed?

text = string.scan( %r{ skip_this ( keep_this ) skip_this }is )
text = text[ 0 ]

Thanks for any help,
Chris