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SketchyLISP
Reference
  Copyright (C) 2007
Nils M Holm

member

Conformance: R5RS Scheme

Purpose: Return the sublist starting at the first member of a list that is equal to a given datum. If no such member exists, return #f.

Arguments:
X - datum to find
A - list

Implementation:

(define (member x a)
  (cond ((null? a) #f)
    ((equal? (car a) x) a)
    (else (member x (cdr a)))))

Example:

(member '(c d) '(a b (c d) e f)) 
=> ((c d) e f)

See also:
memq, memv, assoc.