Team,

I copied the code listed below and attempted to run it. It crashes with the
following messages.

ruby arrow000.rb
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:625:in
`block in arrow': undefined method `*' for nil:NilClass (NoMethodError)
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:569:in
`instance_eval'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:569:in
`block in shapebase'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:573:in
`call'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:573:in
`shapebase'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:593:in
`shape'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/app.rb:624:in
`arrow'
    from arrow000.rb:12:in `block in <main>'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/main.rb:98:in
`instance_eval'
    from
/usr/local/lib/ruby/gems/1.9.1/gems/green_shoes-1.1.374/lib/shoes/main.rb:98:in
`app'
    from arrow000.rb:2:in `<main>'




require "green_shoes"
Shoes.app {
        fill red
        rect(
          :left => 10,
          :top => 10,
          :width => 40
        )
        arrow(
          :left => 30,
          :top => 60,
          :width => 40
        )
      }

Thank you

-- 
Ruby Student