include "dict.m";
dict := load Dictionary Dictionary->PATH;

Dict: adt {
	add: fn(d: self ref Dict, e: (string, string));
	delete: fn(d: self ref Dict, k: string);
	lookup: fn(d: self ref Dict, k: string): string;
	keys: fn(d: self ref Dict): list of string;
};

d.add(e)

Adds a new tuple e to the list, representing a new (key , value) pair.

d.delete(k)

Deletes all pairs with key k from the list.

d.lookup(k)

Tries to find a pair with key k and returns its associated value, or nil if the key was not found.

d.keys()

Returns a list of all keys in the list.

Computational overhead of lookup and deletion of keys is proportional to the number of pairs in the list.