Ruby Intro (mile/km conversion script)

#!/bin/ruby

#notice that this script uses 3 different kinds of commenting mechanisms. Can you spot all three?

#'puts' is like 'print' but also adds a newline
puts "convert from mile or km?"
#gets asks the user for input and saves it as a string in the local variable 'theScale'
theScale = gets
puts "how many?"
#gets still saves the users input as a string, even though they input a number
theNumber = gets

=begin
because 'theNumber' is a string and not an integer, we have to first convert 'theNumber' to an integer using '.to_i' in order to do math on it;
then we '.chomp' on the variable 'theScale' so we can test it for equivalence.
Without chomping, the string would have some extra bites on the end that would make our equivalence test fail
=end

theAnswer = (theNumber.to_i / 5.0 * 8) if theScale.chomp == "mile"
theAnswer = (theNumber.to_i / 8.0 * 5) if theScale.chomp == "km"

#find out more at http://learnrubyonthemac.com
puts "The answer is #{theAnswer}" #try figuring out how to add the distance unit to the end! :)