std.d.lexer: pre-voting review / discussion

[deadalnix]

We are talking about parameters here, not arguments. But overall, 
that isn't the point.

If I have int a = 3 as an argument in the first set of (), I 
still have no clue if it is a runtime or compile time parameter. 
But ref int a = 3 ?

Doing so, you ends up with a lot of ambiguous node (like 
FunctionArgumentOrValueTemplateParameter) and have to manage that 
complexity, or have to backtrack on the parsing and fix ambiguous 
node when you have enough information.