diff options
| -rw-r--r-- | lisp/subr.el | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/lisp/subr.el b/lisp/subr.el index ebf35337bb3..ca75c9f97a3 100644 --- a/lisp/subr.el +++ b/lisp/subr.el | |||
| @@ -761,10 +761,12 @@ To make a hook variable buffer-local, always use | |||
| 761 | ;; Set the actual variable | 761 | ;; Set the actual variable |
| 762 | (if local (set hook hook-value) (set-default hook hook-value)))) | 762 | (if local (set hook hook-value) (set-default hook hook-value)))) |
| 763 | 763 | ||
| 764 | (defun add-to-list (list-var element) | 764 | (defun add-to-list (list-var element &optional append) |
| 765 | "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet. | 765 | "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet. |
| 766 | The test for presence of ELEMENT is done with `equal'. | 766 | The test for presence of ELEMENT is done with `equal'. |
| 767 | If ELEMENT is added, it is added at the beginning of the list. | 767 | If ELEMENT is added, it is added at the beginning of the list, |
| 768 | unless the optional argument APPEND is non-nil, in which case | ||
| 769 | ELEMENT is added at the end. | ||
| 768 | 770 | ||
| 769 | If you want to use `add-to-list' on a variable that is not defined | 771 | If you want to use `add-to-list' on a variable that is not defined |
| 770 | until a certain package is loaded, you should put the call to `add-to-list' | 772 | until a certain package is loaded, you should put the call to `add-to-list' |
| @@ -773,7 +775,10 @@ into a hook function that will be run only after loading the package. | |||
| 773 | other hooks, such as major mode hooks, can do the job." | 775 | other hooks, such as major mode hooks, can do the job." |
| 774 | (if (member element (symbol-value list-var)) | 776 | (if (member element (symbol-value list-var)) |
| 775 | (symbol-value list-var) | 777 | (symbol-value list-var) |
| 776 | (set list-var (cons element (symbol-value list-var))))) | 778 | (set list-var |
| 779 | (if append | ||
| 780 | (append (symbol-value list-var) (list element)) | ||
| 781 | (cons element (symbol-value list-var)))))) | ||
| 777 | 782 | ||
| 778 | ;;;; Specifying things to do after certain files are loaded. | 783 | ;;;; Specifying things to do after certain files are loaded. |
| 779 | 784 | ||