[PATCH] BitSet.compare fix (was Re: [Ocaml-lib-devel] a bug in BitSet?)

[Janne H. <ja...@hy...>]

Here is a patch that should fix BitSet.compare bugs.  I made a 
relatively extensive tester for it and couldn't find any problems.

The compare now works as if the bitvector was a BigInt.  I am guessing 
that that has been the original intent as well.

Perhaps someone can take a look before I commit the changes?

ciao,
janne

> Compare seems completely broken to me too, at least if one
> expects it to work like you suggest (which is IMHO the
> correct way). 
> 
> It doesn't seem to properly account for the two bitsets
> possibly being of different lengths, it just starts
> comparing at the MSB even if the difference between the
> lengths of the sets is more than a byte. It gets more
> complicated because you can't even use |t1|>|t2| as an
> indication that t1>t2, because there is AFAICT no
> guarantee that the leading bit (or even just one bit in
> the first byte of the representation!) is set.