protected class AbstractTreebankParserParams.RemoveGFSubcategoryStripper
The job of this class is to remove subcategorizations from
tag and category nodes, so as to put a tree in a suitable
state for evaluation. Providing the TreebankLanguagePack
is defined correctly, this should work for any language.
Very simililar to subcategory stripper, but strips grammatical
functions as well.
Does whatever one needs to do to a particular tree.
This routine is passed a whole Tree, and could itself
work recursively, but the canonical usage is to invoke this method
via the Tree.transform() method, which will apply the
transformer in a bottom-up manner to each local Tree,
and hence the implementation of TreeTransformer should
merely examine and change a local (one-level) Tree.