From: GianFranco Bozzetti <gf.bozzetti@...>
Date: 2010-04-09T17:40:13+09:00
Subject: Re: match at least one element of array to another


"Kenneth Eunjung" <ken70r@gmail.com> wrote in message 
news:a0e11eac489f01c9d1d359a71d775b4b@ruby-forum.com...
> Hi is there a simple way to return true if at least one element of an
> array matches at least one element of another array?
>
> For example let's say I have @groups = '4,6'.split(',') and @allowed =
> '1,4'.split(',')
>
> I want these to be true because 4 is in both @groups and @allowed.
>
> Thank you!
> -- 
> Posted via http://www.ruby-forum.com/.
>

array1 & array2 returns a new_ array with elements common to
both arrays.  Test on new_array.size returns true if common
elements exsist, false if not.

@groups  = '4,6'.split(',')
@allowed = '1,4'.split(',')
a = @groups & @allowed      # => [4]
puts a.inspect.to_s     # => [4]
ret = (a.size > 0)
puts ret.to_s       # => true
b = [4,6] & [5,7]
puts b.inspect.to_s # => []
ret = (b.size > 0)
puts ret.to_s       # => false
exit

Hth gfb