splice ARRAY, OFFSET, LENGTH, LIST
splice ARRAY, OFFSET, LENGTH
splice ARRAY, OFFSET

This function removes the elements designated by OFFSET and LENGTH fro
+m an array, and replaces them with the elements of LIST, if any. The 
+function returns the elements removed from the array. The array grows
+ or shrinks as necessary. If LENGTH is omitted, the function removes 
+everything from OFFSET onward. The following equivalences hold (assum
+ing $[ is 0):

Direct Method        Splice Equivalent
--------------------------------------------------- 
push(@a, $x, $y)    | splice(@a, $#a+1, 0, $x, $y) 
pop(@a)             | splice(@a, -1) 
shift(@a)           | splice(@a, 0, 1) 
unshift(@a, $x, $y) | splice(@a, 0, 0, $x, $y) 
$a[$x] = $y         | splice(@a, $x, 1, $y); 

The splice function is also handy for carving up the argument list pas
+sed to a subroutine. For example, assuming list lengths are passed be
+fore lists:

sub list_eq {       # compare two list values
    my @a = splice(@_, 0, shift);
    my @b = splice(@_, 0, shift);
    return 0 unless @a == @b;       # same len?
    while (@a) {
        return 0 if pop(@a) ne pop(@b);
    }
    return 1;
}
if (list_eq($len, @foo[1..$len], scalar(@bar), @bar)) { ... }
It would probably be cleaner just to use references for this, however.
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