Emacs -- a non-C function for `vertical-motion` - - i.e., elisp

Question

I'm looking for an elisp function that is the equivalent of the one written in C for vertical-motion.

I would like to implement my own bug-fixes caused by whitespace-mode [(setq whitespace-style '(face space-mark tab-mark newline-mark) )] and visual-line-mode and perhaps some other contributing factors (e.g., linum-mode and tabbar-mode) -- e.g., when point is one more or one less than it should be; or when the last word in a line gets wrapped because the end of line is exactly equal to the window-width (and vertical-motion doesn't know the word has been wrapped).

It is still premature to file a bug report, so I thought I'd try to fix the function instead of creating several contingency plans as bug workarounds -- e.g., if (vertical-motion 0) should place (point) at (window-start) but (point) ends up being one more than it should be, then pretend (point) is really one less.

Answer 1

vertical-motion is a complex function. Re-implementing it in Elisp would be difficult/impossible. Better just report the problems you see as bugs.