Good Haskell Style

[Simon Marlow]

Thomas Schilling wrote:
> 
> On 2 aug 2007, at 12.10, Simon Marlow wrote:
>> While we're on emacs... I know I can colour trailing whitespace 
>> differently, but that's just annoying.  What I want is: on lines that 
>> I edit, remove the trailing whitespace (and if I undo the edit, put 
>> the whitespace back too).  Is there something that does that?  I 
>> couldn't find it.
> 
> The simplest thing I can think of, is to not remove whitespace at all, 
> but to only remove it when you're saving the file.  I know that some 
> modes use such a save hook.  It also wouldn't modify the actual file 
> (ie, don't remove the whitespace until you save the file for the first 
> time), as long as you edit it.  The only time the spaces would be 
> removed permanently were if you save the file, close the buffer, and 
> then re-open the file.
> 
> If I can come up with a simple solution, I'll let you know.

I don't actually want it done on the whole file, which is why I asked for 
the behaviour only on lines that I edit.  The idea is to be 
revision-control-friendly by not introducing unrelated formatting changes.

You could start by removing all the trailing whitespace in all the sources 
in the repository, but I think that's unnecessary.  Also I don't want to be 
forced to do this everywhere.

Cheers,
	Simon