Usage of current-buffer in emacs?

I'm using emacs and I have written a script which uses "current-buffer". However the emacs system doesn't recognise 开发者_如何学编程"current-buffer". When I try "M - x current-buffer" i get the response:

no match

: Any idea what I'm doing wrong?

current-buffer is not an interactive function. That is, can't be invoked interactively via M-x as you've tried to do. You can execute non-interactive lisp-code directly by using eval-expression as follows:

M-: (current-buffer) RET

Notice that you have to enter a proper lisp expression. If you want to capture the value in a variable, something like this

M-: (setq xyzzy (current-buffer)) RET

will store the current buffer into the variable xyzzy.

Do I interpret you correct that you have created a function named current-buffer that you want to be available with M-x current-buffer?

To enable functions to be called by M-x function-name the function needs to be marked as interactive.

A sample from the emacs manual:

(defun multiply-by-seven (number)       ; Interactive version.
       "Multiply NUMBER by seven."
       (interactive "p")
       (message "The result is %d" (* 7 number)))

The (interactive "p") part makes the function callable from the minibuffer (through M-x).

I sounds like you would (also) like to know how to get the name of the current buffer interactively. Use M-: (buffer-name).