I think the idea of the hygenic macro is to implement the macro facility in to the compiler as a change to the parse tree rather than a change to the program text with a preprocessor(sorry if I'm being painfully obvious here).

This means that your macros don't have the normal problems associated with macros(precedence problems, multiple evaluation of arguments etc.). I haven't put very much thought into this, but from I'm guessing an implementation would act like a simplified yacc that worked with the compiler directly.

Again I'm not sure how practical this would be. The only implementation I know of, in scheme, is aided by scheme's use of prefix notation. Figuring out the precedence order would be a pain.

Thoughts?

Noah