Vi fixes

[naryl]

Fixing some discrepancies with vim as I stumble upon them.

Fixed:

• C-u/C-d should scroll half a page by default and preserve cursor location relative to window.
• % when not on a paren should find the following paren on the same line and then do its jump.

Found, not fixed:

• ` is not implemented.
• () and {} motions are not implemented.

[naryl]

C-u/C-d depends on this: #1556

[naryl]

{} are already implemented, they just get overriden by paredit-mode. This makes them work properly:

(define-key lem-paredit-mode:*paredit-mode-keymap* "{" nil)
(define-key lem-paredit-mode:*paredit-mode-keymap* "}" nil)
(define-key lem-vi-mode:*insert-keymap* "{" 'lem-paredit-mode:paredit-insert-brace)
(define-key lem-vi-mode:*insert-keymap* "}" 'lem-paredit-mode:paredit-close-brace)

I feel like there should be a better way to make vi-mode and paredit-mode be nice to each other.

[cxxxr]

Oh, I realized after merging that changing point-charpos breaks encapsulation.
I think it would be better to use line-end-p and character-offset instead.

[naryl]

Ok, I'll do it within 24h. Thanks!

[naryl]

Would it still a problem with temporary point? Like (with-point ((point (copy-point point))) ...)

[cxxxr]

yes, but copy-point is not necessary because it is used automatically with-point.
(with-point ((point point)) ...)

[naryl]

(apropos "line-end-p") doesn't find anything. There's a struct line-end-item-p but I don't think it's what I need here.

[cxxxr]

Sorry, it was end-line-p.