export declare class CronParser { expression: string; dayOfWeekStartIndexZero: boolean; monthStartIndexZero: boolean; constructor(expression: string, dayOfWeekStartIndexZero?: boolean, monthStartIndexZero?: boolean); parse(): string[]; parseSpecial(expression: string): string; protected extractParts(expression: string): string[]; protected normalize(expressionParts: string[]): void; protected validate(parsed: string[]): void; protected validateRange(parsed: string[]): void; protected assertNoInvalidCharacters(partDescription: string, expression: string): void; }