Macro: MATCH

Documentation

Attempts to match the next input character with one of the supplied matchers.

Source

(defmacro match (&rest matchers)
  "Attempts to match the next input character with one of the supplied matchers."
  `(let ((c (peek-stream (state-stream s))))
    (and
     (or ,@(loop for m in matchers
                 collect (etypecase m
                           (standard-char `(char= ,m c))
                           (symbol `(,m c)))))
     ;; cheat here a little bit - eat entire char entity instead
     ;; of peeked char
     (read-stream (state-stream s)))))