check-links.scm

(define srfi-names
  (with-input-from-file "srfi-179.scm"
    (lambda ()
      (let loop ((obj (read)))
	(if (not (and (list? obj)
		      (not (null? obj))
		      (eq? (car obj)
			   'with-output-to-file)))
	    (loop (read))
	    (let ((result '()))
	      (define (process obj)
		(if (list? obj)
		    (cond ((and (not (null? obj))
				(eq? (car obj)
				     'format-lambda-list))
			   (set! result (cons (car (cadadr obj))
					      result)))
			  ((and (not (null? obj))
				(eq? (car obj)
				     'format-global-variable))
			   (set! result (cons (cadadr obj) result)))
			  (else
			   (for-each process obj)))))
	      (process obj)
	      result))))))

(define links
  (with-input-from-file "srfi-179.scm"
    (lambda ()
      (let loop ((obj (read)))
	(if (not (and (list? obj)
		      (not (null? obj))
		      (eq? (car obj)
			   'with-output-to-file)))
	    (loop (read))
	    (let ((result '()))
	      (define (process obj)
		(if (list? obj)
		    (if (and (not (null? obj))
			     (eq? (car obj) '<a>)
			     (eq? (cadr obj) href:)
			     (string? (caddr obj))
			     (positive? (string-length (caddr obj)))
			     (eqv? (string-ref (caddr obj) 0) #\#)
			     )
			(set! result (cons (substring (caddr obj) 1 (string-length (caddr obj)))
					   result))
			(for-each process obj))))
	      (process obj)
	      (map string->symbol result)))))))

(define (in-a-not-in-b a b)
  (do  ((a a (cdr a))
	(result '() (if (memq (car a) b)
			result
			(cons (car a) result))))
      ((null? a) result)))

(newline)(pp "SRFI names without links: ")
(pp (in-a-not-in-b srfi-names links))

(newline)(pp "links without srfi-names: ")
(pp (in-a-not-in-b links srfi-names))