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Selector `car'

The abstraction `car' selects the head of a pair:

(define car 
   (lambda (l)
      (l true)))

`car' is equivalent to a function that is passed a list as an argument[*].

The list is invoked as a function with `true' supplied as an argument. `true' by definition is a selector returning the first of two arguments, which in our case is the head of the pair or list.

Georg P. Loczewski 2004-03-05

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