/tutorial/backtracking/tiny_prolog/prolog_atom.e

 1class PROLOG_ATOM
 2inherit
 3	COMPARABLE
 4	HASHABLE
 5	PROLOG_TERM
 6feature
 7	type: INTEGER is type_atom
 8	name: STRING
 9	infix "<"(other: like Current): BOOLEAN is
10		do
11			Result := name < other.name
12		end
13	hash_code: INTEGER is
14		do
15			Result := name.hash_code
16		end
17end