Shooting oneself in the foot using Ruby, pt1

demo.rb

#!/usr/bin/env ruby

current = 'Silver'

if current = 'Gold'
  #        ^ oh no, a mistake! should've been ==
  puts 'Yay! Found gold'
else
  puts "#{current} is not gold"
end

# This is valid Ruby code and the error is very easy to miss unless you run the code and see the warning:
# $ ruby demo.rb
# demo.rb:7: warning: found `= literal' in conditional, should be ==
# Yay! Found gold