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CoffeeScript

class Bartender
    drinkName: -> 'Manhattan'

    # callback and @, use arrow the fat
    bourbonCallback: => "Maker's Mark #{@drinkName()}"
    
    # yup, use the fat arrow again
    ryeCallback: => "Bulleit Rye #{@drinkName()}"
    
    # callback and no @, so no fat!
    oldCrowCallback: -> "How about a Bud Light instead?"

# simple callback -- will alert the result of the fuction you pass in
callbacker = (callback) -> alert(callback())

bartender = new Bartender()

callbacker(bartender.bourbonCallback)
callbacker(bartender.ryeCallback)
callbacker(bartender.oldCrowCallback)