[Xapian-devel] Apply new format for doclen chunk

[Olly Betts]

On Tue, May 27, 2014 at 10:35:15AM +0800, Hurricane Tong wrote:
> I am trying to apply new format for doclen chunk.
> 
> In class BrassPostList, 
> I am going to add a bool variable is_doclen_chunk, 
> In each function of BrassPostList, I deal with the condition when
> is_doclen_chunk is true.
> Of course some functions don't need changing.

That's probably OK for now.  I think the two cases are likely to end up
sufficiently different that it would make more sense to have a subclass
of BrassPostList specific to doclengths (e.g.  BrassDocLenPostList), but
it's hard to really know.

> And in class BrassPostListTable,
> get_doclength and document_exists don't need changing.
> I am going to rewrite merge_doclen_changes.

OK.

> I also need to modify get_chunk, dealing with the case when the
> parameter tname is empty.

Or perhaps have a separate function if the code isn't at all similar
now.

> In this way, it seems I just need to modify brass_postlist.h and
> brass_postlist.cc.
> Is my understanding correct?

That sounds plausible.  Certainly the changes should be confined to the
brass backend.

Cheers,
    Olly