Metaprogramming Terminators

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Episode 10 - Meta Terminator

Meta Programming in Ruby

#class GoodTerminator
#  likes_to_protect [:john_connor, :sarah_connor]
#  likes_to_destroy []
#end
#
#class BadTerminator
#  likes_to_protect []
#  likes_to_destroy [:john_connor, :sarah_connor]
#end

Panda Level

  1. Implement a method "protects?" where you can pass in the name of a person to check if he protects them
  2. Create a method in the Terminatorable module called "good?" that will tell if a Terminator is good or bad
  3. Create a spec that if the Terminator is trying to destroy someone, they are bad

Tiger Level

  1. Create the GoodTerminator and BadTerminator classes
  2. Update the specs to test the GoodTerminator and Bad Terminator

Eagle Level

  1. Split the methods into likes_to_protect and likes_to_destroy
  2. Alternatively, rename to configuration that accepts a hash of people to protect and people to destroy

Copyright

Copyright: 2012 Jesse Wolgamott, MIT License (See LICENSE)

Metaprogramming Terminators

  • Area:

    Databases  
  • Runtime:

    45  
  • Tech:

    Ruby  
  • Tags:

    RSpec meta eval  

OK, so if you've heard of Ruby described as "powerful" it's because of the ability to change and morf itself at runtime. We call this "Meta Programming" and is pretty unique.

This week, we delve into Meta Programming and try to create a Terminator that can either be good or evil, depending on which movie he's starring in.

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