mauke from the Freenode IRC channel has contributed a vim version:
http://gist.github.com/454255
On 26 June 2010 12:25, Christopher Done
I whipped up a little Emacs script to align the import lines in the current buffer. I am using it in my projects and have experienced no problems. It's good at keeping within 80 columns.
I've pasted it as a gist on Github so that anyone can edit it, gists also provide a simple revision history and comment support. Please feel free to contribute some tweaks and fixes. I'll then see about merging this into haskell-mode in some fashion.
It doesn't handle multiple line explicit imports as I have a personal rule that any explicit import list with more than a few symbols should be changed to an "as X" import, as an addition to tibbe's style guide.[1]
I haven't decided on a recommended keybinding. I'm considering a context-dependent binding of C-c C-. that indents the import list when you are on an import line.