What I was thinking about is possibility to change ParseTree
struct with user-defined version of it. And I was thinking about
setting tree type as template parameter to grammar:
grammar!(MyParseTree)("
Arithmetic:
...
");
Or somethink like this. I think changing source code of library
in order to change tree type is not good and should be set as
parameter. If it's already implemented please let me knoe because
I couldn't find it. And also some minimal interface is needed to
be described in documentation for ParseTree (may be ability to
set it as class is good in order to have polymorthic nodes with
different methods and properties).
Of course I can transform PEGGED syntactic tree into another form
of tree specified by usage domain. But if it doesn't
significantly differs from PEGGED tree (for example node have a
pair of additional properties) it only causes into additional
memory consumption and CPU to transform tree. But if domain
specific tree differs a lot of course we need some useful way to
transform trees.
