I am trying to have a dynamic prompt from my elisp function. I want something like replace-regexp where it will show you the last regexp entered. I tried (interactive (concat "sab" "bab"))) that doesnt work!
I also tried message like format (interactive "s %s" last-used-regexp)
and that doesn't work! Anyone know how to do this?
Thank you!
M-x find-function is your friend. It will tell you how anything in emacs works by showing you the source code. Using it, I find that query-regexp-replace calls query-replace-read-args which calls query-replace-read-from which calls read-from-minibuffer using a prompt created from the last used regexp, which is saved in the dotted pair query-replace-defaults.
So:
(defun my-func ()
"Do stuff..."
(interactive)
(read-from-minibuffer "Regexp? " (first query-replace-defaults)))
is a command that throws up a prompt with the last entered regexp as the default.
Use a variable for input history, and interactive with a list:
(defvar my-func-history nil)
(defun my-func (str)
(interactive (list (read-from-minibuffer "Input string: " (car my-func-history) nil nil 'my-func-history)))
(insert str))
If you don't want the last value entered in there initially, change the (car my-func-history) to nil. You can of course up/down arrow to go through the history at the prompt.
