More Ruby Surprises (and my first Ruby Disappointment)

I'm still going at the PickAxe book. This time it's arrays...

Ruby Surprise B1 - You can use negative indexes

If I use a negative index as the index to your array, it works, but you count from the right hand end, rather than the left:

Ruby Surprise B2 - No ArrayIndexOutOfBoundsException

If I blow the bounds on my array, I just get a nil, rather than an ArrayIndexOutOfBoundsException equivalent:

Ruby Surprise B3 - Addressing Ranges is Easy

There are a number of ways to get a range of values from my array. The first is to pass in two arguments, the start index and the range size:

Then there is the start index and the end index version...:

Or the start index and the one before the end index version...:

And I can even use the negative indexing paradigm as mentioned in Surprise B1...:

Ruby Dissapointment 1 - You can't Count Backwards Through an Array (but Groovy can)

This works in Groovy (which I am learning from a colleague has a very similar syntax to Ruby) but not Ruby: