I've been working through the ruby classes, all very fine stuff
I think this example (taken directly from the course) is taking the refactoring too far (hint: I'm looking at the two "n must be ... " lines)
# Check for correct input!
"n must be an integer" unless n.is_a? Integer
"n must be greater than 0" if n <= 0
# The Ruby 1.9 Prime class makes the array automatically!
prime = Prime.instance
when called thus:
the code just hangs (or presumably tries to find the first -10 primes .
When I add back the "return" statements before "n must be ... " then it works as expected.