func (l *icmpPacketList) Front() *icmpPacket {
	return l.head
}
Front returns the first element of list l or nil.
package icmp
type icmpPacketElementMapper struct{}
func (icmpPacketElementMapper) linkerFor(elem *icmpPacket) *icmpPacket { return elem }
type icmpPacketList struct {
	head *icmpPacket
	tail *icmpPacket
}
func (l *icmpPacketList) Reset() {
	l.head = nil
	l.tail = nil
}
func (l *icmpPacketList) Empty() bool {
	return l.head == nil
}