On Mar 1, 2006, at 3:13 PM, cremes.devlist / mac.com wrote:

> I was intrigued by the post that _why put up a few days/weeks ago  
> about using case/when for testing arrays [1]. I thought I'd give it  
> a try but I can't make it work. What am I doing wrong?
>
> irb(main):001:0> r1 = (0..12).to_a
> => [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
> irb(main):002:0> r2 = (20..32).to_a
> => [20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32]
> irb(main):003:0> def foo range
> irb(main):004:1>  case range
> irb(main):005:2> when *r1
> irb(main):006:2>   puts "#{range} in r1"
> irb(main):007:2> when *r2
> irb(main):008:2>   puts "#{range} in r2"
> irb(main):009:2> else
> irb(main):010:2*   puts "#{range} NOT in any range"
> irb(main):011:2> end
> irb(main):012:1> end
> => nil
> irb(main):013:0> foo 3
> NameError: undefined local variable or method `r1' for main:Object
>         from (irb):5:in `foo'
>         from (irb):13

Responding to my own email...

I figured it out about 5 minutes after sending. This is purely a  
scope mistake on my part. Variables r1 and r2 are NOT in scope inside  
foo which is exactly what ruby told me.

The fix is to make r1 and r2 into class vars. Change r1 to @r1 and r2  
to @r2 in that example and it works just fine.

Nuby making lots of mistakes!