(def return (new-parse-position return-value) (list new-parse-position return-value)) (def match (f) (only (fn (p) (let x car.p (if (f x) (return cdr.p x)))))) (def alt parsers (fn (p) (some [_ p] parsers))) (def seq parsers (fn (p) ((afn (p parsers a) (if parsers (iflet (p2 r) (car.parsers p) (self p2 cdr.parsers (cons r a))) (return p rev.a))) p parsers nil))) (def many (parser) (fn (p) ((afn (p a) (iflet (s2 r) (parser p) (self s2 (cons r a)) (return p rev.a))) p nil))) (def on-result (f parser) (fn (p) (iflet (p2 r) (parser p) (return p2 (f r))))) (mac with-result (vars parser . body) `(on-result (fn (,vars) ,@body) ,parser)) (mac with-seq (vars-parsers . body) (withs (ps (pair vars-parsers) vars (map car ps) parsers (map cadr ps)) `(on-result (fn (,vars) ,@body) (seq ,@parsers)))) (def cons-seq (a b) (with-seq (r a rs b) (cons r rs))) (def many1 (parser) (cons-seq parser (many parser))) (def must (errmsg parser) (fn (p) (or (parser p) (err errmsg)))) (def seqi (i parsers) (with-result results (apply seq parsers) (results i))) (def seq1 p (seqi 0 p)) (def seq2 p (seqi 1 p)) (def optional (parser) (alt parser (fn (p) (return p nil)))) (mac forward (parser) (w/uniq p `(fn (,p) (,parser ,p)))) (def match-is (x) (match [is x _])) (def match-literal (pat val) (with (patlist (coerce pat 'cons) patlen len.pat) (fn (p) (if (begins p patlist) (return (nthcdr patlen p) val))))) (def parse-intersperse (separator parser must-message) (optional (cons-seq parser (many (seq2 separator (must must-message parser)))))) (def skipw (p) (mem nonwhite p)) (def skipwhite (parser) (fn (p) (parser (skipw p)))) (def comma-separated (parser must-message) (parse-intersperse (skipwhite:match-is #\,) parser must-message))