[Xapian-devel] How the matcher knows when to prune and decay

[Olly Betts]

On Tue, Mar 02, 2010 at 10:55:24PM -0500, Matt Chaput wrote:
> So I'm wondering, how does the matcher know the maximum score of the rest of
> the postings in a branch?

It asks the subtree for its maximum score, which the subtree calculates
recursively.

That maximum can decrease during the matching process - for example, when a
child of OP_OR reaches its end.

Cheers,
    Olly