On Mar 17, 12:49 pm, John Honovich <jhonov... / gmail.com> wrote:
> I want to pull a list of terms and use them to scan documents to
> determine if any of those words are present.
>
> Let's say fruits = ["apples","oranges","grapes"].
>
> I do Regexp.union(*fruits).  This returns /apples|oranges|grapes/ which
> is good.
>
> Now I want this pattern to be case insensitive, i.e. -
> /apples|oranges|grapes/i
>
> Docs say I can set each argument to case insensitive and then call union
> e.g. - Regexp.union(/dogs/, /cats/i)        #=>
> /(?-mix:dogs)|(?i-mx:cats)/
>
> I have been doing fruits.map!{|fruit| Regexp.new(fruit,
> Regexp::IGNORECASE)}; Regexp.union(*fruits)
>
> This seems to work.  Is there any better or cleaner way to do this?
>
> Thanks,
>
> John
> --
> Posted viahttp://www.ruby-forum.com/.

I don't know how much better this is, but you could union first, then
add the case-insensitivity:

fruits = ["apples","oranges","grapes"]
r = Regexp.union(*fruits)
r = Regexp.new(r.source, Regexp::IGNORECASE)  # => /apples|oranges|
grapes/i

HTH,
Chris