How can I evaluate a line of Python code from emacs buffer and have the result be written to the buffer at my cursor? I want to do something like in haskell-mode where you can type C-u C-c C-t and the type definition of whatever was at your cursor is inserted at your cursor.
So, if I selected and sent a region such as
1 + 2
from a .py buffer to the Python inferior process I would then see
3
1 + 2
in my .py buffer, ie. the 3 followed by a newline was inserted at point.
To insert the result of a shell command at point we have C-u M-! (shell-command), so you can insert the result of a python command with python -c "print 1 + 2".
To take the current line would need a bit of lisp. Here a very simple example.
(defun my-py-eval-insert-current-line ()
"Eval the current line and insert its result."
(interactive)
(setq cmd (read-from-minibuffer "Python cmd: " (format "python -c 'print %s'" (current-line))))
(setq res (shell-command-to-string cmd))
(insert res)
)
with
(defun current-line ()
"returns the current line."
;; http://ergoemacs.org/emacs/elisp_all_about_lines.html
(let (p1 p2 myLine)
(setq p1 (line-beginning-position) )
(setq p2 (line-end-position) )
(setq myLine (buffer-substring-no-properties p1 p2))
))
I would rather look at pymacs for something serious.
ps: elisp functions: http://wikemacs.org/wiki/Emacs_Lisp_Cheat_Sheet
org-mode, i.e. org-babel provides a similar thing, which seems worth testing.
Current trunk of python-mode.el
https://launchpad.net/python-mode
offers an option py-store-result-p
When t, result is accessible in car of kill-ring - next yank inserts it.
You may define a command which reads (car kill-ring) for insert.
Also a feature request there should have some chances.
