reader macro

[jdn]

Is there any equivalent to a reader macro in nim? I wrote an expression parser 
and evaluator in nim which was very easy to do. To get better performance I 
thought that since nim has macro's I can leverage that without too much 
trouble. However, walking the AST of my expression parser to create nim AST (in 
macros) requires compile time proc's for recursion and so I have a chicken and 
egg problem that I can't seem to resolve.