NAME
    null - null value

SYNOPSIS
    null()

TYPES
    return	null

DESCRIPTION
    There is only one value of null type.  After x = null(), isnull(x)
    returns 1 but isreal(x). isnum(x), etc. all return zero, and
    x == y is true if and only if y is also null.  The null value
    tests as false in conditions.

    The null value is the value returned by some functions, e.g.
    x = printf("%d\n", 27) assigns to x the null value.  If L is a
    list with no elements (given by L = list()), then both pop(L)
    and remove(L) return the null value.

    The null value may be used as an argument in some operations, e.g.
    for any x, x + null() returns x.

EXAMPLE
    In a print statement like

	print 2, null(), 3;

    or

	printf("%d %d %d\n", 2, null(), 3);

    the null value produces no output.  Both of these examples
    print the same as both

	print 2, null(), 3;

    and

	print "2  3";

LIMITS
    none

LIBRARY
    none

SEE ALSO
    XXX - missing
