NAME
    select - form a list by selecting element-values from a given list

SYNOPSIS
    select(x, y)

TYPES
    x		list
    y		string

    return	list

DESCRIPTION
    If y is to be the name of a user-defined function, select(x, y)
    returns a list whose members are the values z of elements of x
    for which the function at z tests as nonzero.
    The list x is not changed.  The order of the returned list is
    the same as in x.


EXAMPLE
    > define f(x) = x > 5
    > A = list(2,4,6,8,2,7)
    > print select(A, "f")

    list (3 elements, 3 nonzero):
	  [[0]] = 6
	  [[1]] = 8
	  [[2]] = 7

LIMITS
    none

LIBRARY
    none

SEE ALSO
    XXX - fill in
