combineConditionsOr(conditions) {
		if (conditions.length === 0) {
			return {
				matchWhenEmpty: false,
				fn: () => false
			};
		} else if (conditions.length === 1) {
			return conditions[0];
		}
		return {
			matchWhenEmpty: conditions.some(c => c.matchWhenEmpty),
			fn: v => conditions.some(c => c.fn(v))
		};
	}
@param {Condition[]} conditions some conditions
@returns {Condition} merged condition