Scheme Request for Implementation 257, "Simple extendable pattern matcher with backtracking", by Sergei Egorov, is now available for discussion.
Its draft and an archive of the ongoing discussion are available at https://srfi.schemers.org/srfi-257/. You can join the discussion of the draft by filling out the subscription form on that page. You can contribute a message to the discussion by sending it to [email protected]. Here's the abstract: Pattern matching extends Scheme's repertoire of conditional constructs, allowing decomposition of compound data structures and binding their parts to variables. This SRFI proposes one such construct, match, which provides all common-denominator functionality described in SRFI-200 <https://srfi.schemers.org/srfi-200/>, adding on top of it support for non-linear patterns and backtracking. Also, the proposed construct is modular, and allows for convenient extension via the define-match-pattern mechanism. Regards, SRFI Editor
