(help-xref-on-pp): New function.

(describe-variable): Use it to display xrefs in a symbol's value.

diff --git a/lisp/help.el b/lisp/help.el
index 12ef3ab81e233ce01b39c98aee0d74beb6cab302..fed3dd7f691d29e8f3a97e73ce04ba3862a8a2d4 100644 (file)
--- a/lisp/help.el
+++ b/lisp/help.el
@@ -751,6 +751,29 @@ Return 0 if there is no such symbol."
          (set-syntax-table stab)))
     (error 0)))
 
+(defun help-xref-on-pp (from to)
+  "Add xrefs for symbols in `pp's output between FROM and TO."
+  (let ((ost (syntax-table)))
+    (unwind-protect
+       (save-excursion
+         (save-restriction
+           (set-syntax-table emacs-lisp-mode-syntax-table)
+           (narrow-to-region from to)
+           (goto-char (point-min))
+           (while (not (eobp))
+             (cond
+              ((looking-at "\"") (forward-sexp 1))
+              ((looking-at "#<") (search-forward ">" nil 'move))
+              ((looking-at "\\(\\(\\sw\\|\\s_\\)+\\)")
+               (let* ((sym (intern-soft
+                            (buffer-substring (match-beginning 1) (match-end 1))))
+                      (fn (cond ((fboundp sym) #'describe-function)
+                                ((and sym (boundp sym)) #'describe-variable))))
+                 (when fn (help-xref-button 1 fn sym)))
+               (goto-char (match-end 1)))
+              (t (forward-char 1))))))
+      (set-syntax-table ost))))
+
 (defun describe-variable (variable)
   "Display the full documentation of VARIABLE (a symbol).
 Returns the documentation as a string, also."
@@ -772,20 +795,27 @@ Returns the documentation as a string, also."
          (if (not (boundp variable))
              (progn
                (princ " is void")
-               (terpri)
                (setq valvoid t))
-           (princ "'s value is ")
-           (terpri)
-           (pp (symbol-value variable))
-           (terpri))
+           (let ((val (symbol-value variable)))
+             (with-current-buffer standard-output
+               (princ "'s value is ")
+               (terpri)
+               (let ((from (point)))
+                 (pp val)
+                 (help-xref-on-pp from (point))))))
+         (terpri)
          (if (local-variable-p variable)
              (progn
                (princ (format "Local in buffer %s; " (buffer-name)))
                (if (not (default-boundp variable))
                    (princ "globally void")
-                 (princ "global value is ")
-                 (terpri)
-                 (pp (default-value variable)))
+                 (let ((val (default-value variable)))
+                   (with-current-buffer standard-output
+                     (princ "global value is ")
+                     (terpri)
+                     (let ((from (point)))
+                       (pp val)
+                       (help-xref-on-pp from (point))))))
                (terpri)))
          (terpri)
          (save-current-buffer