From: timr <timrandg@...>
Date: 2010-08-27T15:32:29+09:00
Subject: how about Array#collect_until

I am wondering if anyone has implemented an Array#collect_until method
to break out of a collect loop after an end-point has been achieved
during an Array#collect call.

For instance, you have a long array of items and want to use each item
to calculate something, but should the calculation give a specific
result, then you know you are done--no need for processing the rest of
the array. However, if that specified result is not met, the
processing continues. Something like below:

[1,2,3].collect{|item| item + 10} # => [11,12,13]
[1,2,3].collect_until({|x| x%2 == 0}) {|item| item + 10} # => [11,12]

To get this to work the result from the yield to {|item| item + 10}
block would be run through the {|x| x%2 == 0} block to check if we are
done.

Thanks for any suggestions.