gistfile1.sls

(define-syntax (lexer-src-pos-kw s)
    (define (char->ci-pattern c)
      (list ':or (char-downcase c) (char-upcase c)))
    
    (define (string->ci-pattern s)
      (if (symbol? s)
          (string->ci-pattern (symbol->string s))
          (cons ':: (map char->ci-pattern (string->list s)))))
    
    (define (token-name s)
      (if (symbol? s)
          (token-name (symbol->string s))
          (string-append "token-" (string-upcase s))))
    
    (define (token-names l)
      (map (λ (s) (string->symbol (token-name s))) (syntax->datum l)))
    
    (syntax-case s ()
      ((_ (kw ...) ((sm n) ...) forms ...)
       (with-syntax ([(seq ...) (map string->ci-pattern 
                                     (syntax->datum (syntax (kw ...))))]
                     [(token-x ...) (token-names (syntax (kw ...)))]
                     [(token-n ...) (token-names (syntax (n ...)))])
         (syntax (lexer-src-pos 
                  (seq (make-kw-tk token-x lexeme))...
                  (sm (make-kw-tk token-n lexeme))...
                  forms ...))))))