erezsh/plyplus — pull request #6 by ray-harris-net (2013-03-27 03:50:07+00:00)
Title: Added keep_empty_trees option to Grammar() class

I added an option to the Grammar() class that allows the user to determine whether empty sub-trees in the AST tree will be kept or discarded. I set it to True by default.

I also added a JSON parser example that needs empty sub-trees kept as JSON allows empty objects and arrays as part of its grammar.