On Mon, Dec 05, 2011 at 10:27:08AM +1100, Chris Rosengren wrote:

Over the last few weeks I have been learning elisp and implementing hooks into slime-mode so that vim bindings feel more natural there. Here is an example

(defun slime-repl-bol-insert () (interactive) (slime-repl-bol) (evil-insert 1)

Then I would add this too a slime-repl-mode-hook

(define-key evil-normal-state-map "I" 'slime-repl-bol-insert)

I'm attempting to make all commands such as I, 0, etc work to the start of the REPL prompt rather than the beginning of the line. I think this has implications not only for repl/inferior modes but dired/term/eshell modes as well.

I have two questions, is this general approach i'm taking reasonable - defining functions that overwrite the generic bindings, and adding them in hooks to slime-mode/eshell-mode etc?

This is certainly a valid approach. Although it may be preferable to use `evil-define-key' or `evil-declare-key' to install the key-bindings for special modes/keymaps or use `evil-normal-state-local-map', otherwise you would change the global bindings in all modes, not only in slime-repl-mode.

the second question that I'm having a hard time with involves making dd and yy work correctly, I have browsed the source and it seems they are implemented in motions involving moving to the next line -> what would be a reasonable solution to get say dd to delete everything on a line except the prompt, and yy to yank everything on a line except the prompt.

Currently the internal behavior of evil depends heavily on Emacs functions like `forward-line', `beginning-of-line' and so on, so there is no easy way to make evil ignore some prefix in a line. The only way I could imagine is to redefine evil-change/evil-delete/evil-yank and friends (perhaps evil-change can be left unchanged because it uses the others internally). Those functions are operators which should respect the type of the motion passed to them as argument (i.e., whether the type is char/line/block). I think it should not be too difficult to implement the behavior you desire, but be aware that there may be some pitfalls ... ;) And think of other operators, like `evil-shift-left' which may have similar problems. Frank