Function: gud-perldb-marker-filter

gud-perldb-marker-filter is a byte-compiled function defined in gud.el.gz.

Signature

(gud-perldb-marker-filter STRING)

Source Code

;; Defined in /usr/src/emacs/lisp/progmodes/gud.el.gz
;; There's no guarantee that Emacs will hand the filter the entire
;; marker at once; it could be broken up across several strings.  We
;; might even receive a big chunk with several markers in it.  If we
;; receive a chunk of text which looks like it might contain the
;; beginning of a marker, we save it here between calls to the
;; filter.
(defun gud-perldb-marker-filter (string)
  (setq gud-marker-acc (concat gud-marker-acc string))
  (let ((output ""))

    ;; Process all the complete markers in this chunk.
    ;;
    ;; Here I match the string coming out of perldb.
    ;; The strings can look like any of
    ;;
    ;;  "\032\032/tmp/tst.pl:6:0\n"
    ;;  "\032\032(eval 5)[/tmp/tst.pl:6]:3:0\n"
    ;;  "\032\032(eval 17)[Basic/Core/Core.pm.PL (i.e. PDL::Core.pm):2931]:1:0\n"
    ;;
    ;; From those I want the filename and the line number.  First I look for
    ;; the eval case.  If that doesn't match, I look for the "normal" case.
    (while
        (string-match
         (eval-when-compile
           (let ((file-re "\\(?:[a-zA-Z]:\\)?[^:\n]*"))
             (concat "\032\032\\(?:"
                     (concat
                      "(eval [0-9]+)\\["
                      "\\(" file-re "\\)" ; Filename.
                      "\\(?: (i\\.e\\. [^)]*)\\)?"
                      ":\\([0-9]*\\)\\]") ; Line number.
                     "\\|"
                     (concat
                      "\\(?1:" file-re "\\)" ; Filename.
                      ":\\(?2:[0-9]*\\)")    ; Line number.
                     "\\):.*\n")))
         gud-marker-acc)
      (setq

       ;; Extract the frame position from the marker.
       gud-last-frame
       (cons (match-string 1 gud-marker-acc)
	     (string-to-number (match-string 2 gud-marker-acc)))

       ;; Append any text before the marker to the output we're going
       ;; to return - we don't include the marker in this text.
       output (concat output
		      (substring gud-marker-acc 0 (match-beginning 0)))

       ;; Set the accumulator to the remaining text.
       gud-marker-acc (substring gud-marker-acc (match-end 0))))

    ;; Does the remaining text look like it might end with the
    ;; beginning of another marker?  If it does, then keep it in
    ;; gud-marker-acc until we receive the rest of it.  Since we
    ;; know the full marker regexp above failed, it's pretty simple to
    ;; test for marker starts.
    (if (string-match "\032.*\\'" gud-marker-acc)
	(progn
	  ;; Everything before the potential marker start can be output.
	  (setq output (concat output (substring gud-marker-acc
						 0 (match-beginning 0))))

	  ;; Everything after, we save, to combine with later input.
	  (setq gud-marker-acc
		(substring gud-marker-acc (match-beginning 0))))

      (setq output (concat output gud-marker-acc)
	    gud-marker-acc ""))

    output))