knowitall/taggers — pull request #20 by schmmd (2013-10-17 22:01:54+00:00)
Title: Use Sentence representation

I moved the taggers project forward to use a `Sentence` representation. I had some interesting problems with the constraints on taggers w.r.t. co/contra variance. I reworked this by making a `ConstrainedTagger` and now the code is much simpler (and it also compiles). One scary part is that when you deserialize taggers from strings, you can cast them to a bad type. I.e. you could cast a `PatternTagger` to a `Tagger[Sentence]`.