OK...

so I finally have some time to work on my ElfData plugin again. I've
been busy the past few months but now I can work again.

I've got an early version of the ElfDataTokeniser class working. I've
made an example project that can parse simple mathematical
expressions, including variables like "a", "b", "c". It understands +-/
* and () brackets.

It has some very big limitations.

1) All numbers are processed in order. So 1+2*3=9, and not 7 like
you'd expect.

2) No support for negative numbers. You need to enter (0-3) instead of
-3.

The negative numbers thing I can implement cleanly using my
ElfDataTokeniser, so I'll do that later.

The operator reordering thing... that's not even an ElfDataTokeniser
issue, it's simply an awkward thing to do regardless of the language.
I may just leave it as it is, unless I find a graceful way to do this.

I don't want to create a nice simple clean demo project with 40 lines
of code, to show people how to parse code using my ElfDataTokeniser
class, and then bulk it down with 100 lines of code just to reorder
the operators!

Probably I'll release this by Sunday.