Worldwide Holiday Parser

date-holidays-parser is a JavaScript and TypeScript library designed to parse and calculate worldwide holidays, acting as the rule-engine backbone for the `date-holidays` library. It provides functionalities to determine public, bank, and observance holidays for various countries, states, and regions, adhering to ISO 3166-2 standards. The library is currently at version 3.4.7 and appears to be actively maintained, though no explicit release cadence is stated. Key features include timezone consideration for holiday checks, support for substitute days, multi-language holiday names, and the ability to define custom holidays. It also uniquely integrates support for Islamic, Hebrew, and Chinese calendars, though it cautions about potential inaccuracies with Islamic dates due to moon sighting dependencies. This parser is distinct in its use of a custom grammar for day calculations, enabling precise and flexible holiday determination across diverse cultural and legal frameworks.