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first (FUNCTION)

Format: (first <exp> )

Required arguments: 1

<exp> : any Lisp expression which returns a list

The argument expression must evaluate to a list; first returns the first element of this list. If the list is empty, i.e. is nil, first returns nil.

Examples:

>  (first '(1 2 3))
1

>  (first '((a (b (c)) d) e (f)))
(A (B (C)) D)

>  (first ())
NIL

>  (first 'a)
Error: A is not of type LIST



© Colin Allen & Maneesh Dhagat
March 2007