(symbol-file-load-history-loaded): Variable renamed,

[gnu-emacs] / lisp / help.el

diff --git a/lisp/help.el b/lisp/help.el
index 1347fdf1abfacd07cbe07f3a063e326624f728a4..ddc67c43432fa68a91c800e2659e192675728ebc 100644 (file)
--- a/lisp/help.el
+++ b/lisp/help.el
@@ -541,7 +541,27 @@ C-w Display information on absence of warranty for GNU Emacs."
              (error nil)))
       (set-syntax-table stab))))
 
-(defun describe-function-find-file (function)
+(defvar symbol-file-load-history-loaded nil
+  "Non-nil means we have loaded the file `fns-VERSION.el' in `exec-directory'.
+That file records the part of `load-history' for preloaded files,
+which is cleared out before dumping to make Emacs smaller.")
+
+(defun symbol-file (function)
+  "Return the input source from which SYM was loaded.
+The value is normally a string that was passed to `load':
+either an absolute file name, or a library name
+\(with no directory name and no `.el' or `.elc' at the end).
+It can also be nil, if the definition is not associated with any file."
+  (unless symbol-file-load-history-loaded
+    (load (expand-file-name
+          ;; fns-XX.YY.ZZ.el does not work on DOS filesystem.
+          (if (eq system-type 'ms-dos)
+              "fns.el"
+            (format "fns-%s.el" emacs-version))
+          exec-directory)
+         ;; The file name fns-%s.el already has a .el extension.
+         nil nil t)
+    (setq symbol-file-load-history-loaded t))
   (let ((files load-history)
        file functions)
     (while files
@@ -610,7 +630,7 @@ C-w Display information on absence of warranty for GNU Emacs."
       (princ "("))
     (princ string)
     (or file-name
-       (setq file-name (describe-function-find-file function)))
+       (setq file-name (symbol-file function)))
     (if file-name
        (progn
          (princ " in `")
@@ -749,7 +769,7 @@ Returns the documentation as a string, also."
          ;; Make a hyperlink to the library if appropriate.  (Don't
          ;; change the format of the buffer's initial line in case
          ;; anything expects the current format.)
-         (let ((file-name (describe-function-find-file variable)))
+         (let ((file-name (symbol-file variable)))
            (when file-name
              (princ "\n\nDefined in `")
              (princ file-name)