Tables: module {	PATH: con "/dis/lib/tables.dis";	Table: adt[T] {		items:	array of list of (int, T);		nilval:	T;			new: fn(nslots: int, nilval: T): ref Table[T];		add:	fn(t: self ref Table, id: int, x: T): int;		del:	fn(t: self ref Table, id: int): int;		find:	fn(t: self ref Table, id: int): T;	};		Strhash: adt[T] {		items:	array of list of (string, T);		nilval:	T;			new: fn(nslots: int, nilval: T): ref Strhash[T];		add:	fn(t: self ref Strhash, id: string, x: T);		del:	fn(t: self ref Strhash, id: string);		find:	fn(t: self ref Strhash, id: string): T;	}; 	hash: fn(s: string, n: int): int;};