Feature Request: Expose dataSymbol to enable more effeciently extending ArrayKeyedMap

[mrfigg]

Hi, thanks for the great module!

Would it be possible to expose dataSymbol so that people who want to extend ArrayKeyedMap can access the data values directly in the tree? For the "wildHas" function I am adding I have to search the tree for all matching paths then wrap "has" which is redundant because it searches the tree again. If I had access to dataSymbol I could directly re-implement the data value check.