SYNOPSIS
	object next_inventory()
	object next_inventory(object ob)

DESCRIPTION
	Get next object in the same inventory as ob. If ob is not
	given, the current object will be used.
	
	This efun is mostly used together with the efun
	first_inventory().

SEE ALSO
	first_inventory(E), all_inventory(E), environment(E),
	deep_inventory(E)