Parsimmon Parser Combinator Library

Parsimmon is a compact, monadic LL(infinity) parser combinator library for JavaScript, enabling the construction of complex parsers from smaller, composable units. It is currently at version 1.18.1 and supports both modern Node.js environments and older browser versions (down to IE7). Its release cadence appears to be infrequent, with the last major feature release (1.7.0) being in 2018, though bug fixes and minor updates have occurred more recently. Key differentiators include its inspiration from Haskell's Parsec and Promises/A+ for its API design, its support for binary parsing using Node.js Buffers, and its compatibility with the Fantasy Land specification, implementing several algebraic structures like Semigroup, Apply, Applicative, Functor, Chain, and Monad. It distinguishes itself by offering a functional and declarative approach to parsing, making grammars easy to read and maintain.