From d749491187cdd71459fd5a5e3521fe61556d6860 Mon Sep 17 00:00:00 2001 From: "Kim F. Storm" Date: Tue, 16 May 2006 11:19:39 +0000 Subject: [PATCH] (add-to-history): Add KEEP-ALL arg and align functionality with read-from-minibuffer. --- lisp/subr.el | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/lisp/subr.el b/lisp/subr.el index ee6c468d711..956fcef64f4 100644 --- a/lisp/subr.el +++ b/lisp/subr.el @@ -1123,28 +1123,36 @@ The return value is the new value of LIST-VAR." (< oa ob) oa))))))) -(defun add-to-history (history-var newelt &optional maxelt) +(defun add-to-history (history-var newelt &optional maxelt keep-all) "Add NEWELT to the history list stored in the variable HISTORY-VAR. Return the new history list. If MAXELT is non-nil, it specifies the maximum length of the history. Otherwise, the maximum history length is the value of the `history-length' property on symbol HISTORY-VAR, if set, or the value of the `history-length' variable. -Remove duplicates of NEWELT unless `history-delete-duplicates' is nil." +Remove duplicates of NEWELT if `history-delete-duplicates' is non-nil. +If optional fourth arg KEEP-ALL is non-nil, add NEWELT to history even +if it is empty or a duplicate." (unless maxelt (setq maxelt (or (get history-var 'history-length) history-length))) (let ((history (symbol-value history-var)) tail) - (if history-delete-duplicates - (setq history (delete newelt history))) - (setq history (cons newelt history)) - (when (integerp maxelt) - (if (= 0 maxelt) - (setq history nil) - (setq tail (nthcdr (1- maxelt) history)) - (when (consp tail) - (setcdr tail nil)))) + (when (and (listp history) + (or keep-all + (not (stringp newelt)) + (> (length newelt) 0)) + (or keep-all + (not (equal (car history) newelt)))) + (if history-delete-duplicates + (delete newelt history)) + (setq history (cons newelt history)) + (when (integerp maxelt) + (if (= 0 maxelt) + (setq history nil) + (setq tail (nthcdr (1- maxelt) history)) + (when (consp tail) + (setcdr tail nil))))) (set history-var history))) -- 2.39.5