From the NannyMUD documentation

LAST CHANGE

2001-08-07

FUNCTION

NAME
        debug_info - 


SYNTAX
	int debug_info(int arg, mixed target)

DESCRIPTION
	This function writes a rather extensive set of debug information. The
	argument 'arg' and 'target' can take on several combinations, all of
	which gives different debug information.
	
	On 'success', te value 1 is returned, else 0.

	Arg	Target	Info gained				Return value
	0	object	Rather fat info.			0
	1	object	Less fat info.				0
	2	string	Nr of ref counts for the string		0
	3	int	Info on malloced strings.		0
	4	array	?					nr instances
		mapping	?					nr instances
		string	?					nr instances


NOTE
	It can be rather costly to use.