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22.2.7 List Searching
The following procedures search lists for particular elements. They use
different comparison predicates for comparing list elements with the
object to be searched. When they fail, they return #f
, otherwise
they return the sublist whose car is equal to the search object, where
equality depends on the equality predicate used.
memq x lst

Scheme Procedure 
scm_memq (x, lst)

C Function 
Return the first sublist of lst whose car is eq?
to x where the sublists of lst are the nonempty
lists returned by (listtail lst k) for
k less than the length of lst. If x does not
occur in lst, then #f (not the empty list) is
returned.

memv x lst

Scheme Procedure 
scm_memv (x, lst)

C Function 
Return the first sublist of lst whose car is eqv?
to x where the sublists of lst are the nonempty
lists returned by (listtail lst k) for
k less than the length of lst. If x does not
occur in lst, then #f (not the empty list) is
returned.

member x lst

Scheme Procedure 
scm_member (x, lst)

C Function 
Return the first sublist of lst whose car is
equal? to x where the sublists of lst are
the nonempty lists returned by (listtail lst
k) for k less than the length of lst. If
x does not occur in lst, then #f (not the
empty list) is returned.
