Trie should not be specific to subclasses of AbstractString

[oxinabox]

Tries work find for any collection of elements of a free monoid (I think I have that term right).
Not just strings,
but also things like arrays of Ints.
Technically arrays of Float64s but that causes other problems.

Wikipedia gets several examples on nonstrings.
I haven't have a close look at the code, but it seems like this is simply a matter of relaxing a type constraint.
Particularly since these are uncompressed dict based Tries.

[kmsquire]

@oxinabox, care to take a stab at implementing this?

[rofinn]

I could probably look into this. @oxinabox I'm not very familiar with the term "free monoid" and the wikipedia entry is a bit dense, but would that include Strings or Symbols?

[oxinabox]

Yeah, strings, but symbols (except if you convert them to strings).
We actually don't even need free moniods, thinking about it (because that requires a concat operation)

Basically a try can be indexed with
anything that is a finite-length iterable of elements from a finite set really.

I'm in no hurry for this, it is more of a nice-to-have.
(Otherwise I'ld have implemented it myself)

[rofinn]

@oxinabox Alright, I have a prototype of supporting both AbstractString and Vector{T}. JuliaCollections/Tries.jl#2