id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	revision
23	Arc/Node validity check in ListGraph (and in SmartGraph)	Alpar Juttner	Balazs Dezso	"The possibility of checking the validity of {{{Arc}}}, {{{Edge}}} and {{{Node}}} data structures are very important for creating proper language binding for scripting language. (A language binding must ensure that the user cannot crash the interpreter itself by a faulty code.)

Using {{{SmartGraph}}}, it is easy to check it by checking if the item id is in the corresponding range

For {{{ListGraph}}}, my suggestion would be to set the source of an edge to INVALID when it is deleted. It would cause quite little performance loss and then the validity could be checked in constant time.
"	enhancement	closed	major	LEMON 1.0 release	core	hg main	fixed