class TokenList inherits System {
	token: IToken;
	next: TokenList;

	init(value: IToken, tail: Object) : TokenList {{
		assert(not (isvoid value), "init", "value argument cannot be void!");
		assert(isvoid token, "init", "List has already been initialised!");

		token <- value;
		if isvoid tail then
			void
		else
			case tail of
				tl: TokenList => next <- tl;
				o: Object => assert(false, "init", "tail argument can be either a TokenList or void!");
			esac
		fi;

		self;
	}};

	push(value: IToken) : TokenList {{
		assert(not (isvoid value), "push", "value argument cannot be void!");

		if isvoid token
		then
			token <- value
		else if isvoid next
		then
			next <- (new TokenList).init(value, void)
		else
			next.push(value)
		fi
		fi;
		self;
	}};

	out() : Object {{
		if isvoid token
		then
			void
		else
			out_string("<")
			.out_string(token.name())
			.out_string(">")
		fi;
		if isvoid next
		then
			void
		else {
			out_string(" ");
			next.out();
		}
		fi;
	}};
};