[nem-en] ManagerClass.Instance == pain!

[vc]

> you would need to transform the Utility module to take the context into
> account:
> 
> macro Generate (specification1, specification2) {
>   def code1 = Utility.Generate1 (Macros.Manager(), specification1);
>   def code2 = Utility.Generate2 (Macros.Manager(), specification2);
>   <[ $code1 + $code2 ... ]>
> }
> 
> module Utility {
>   public Generate1 (mgr:ManagerClass, expr : PExpr) : PExpr {     ...
> }
>    private myUtil (mgr:ManagerClass, expr:PExpr):PExpr {  }
>   ...
> }
> 
> and pass it everywhere...

We can put context into [ThreadStatic]-variable. It variable can be
initialized before macro running. Macro can't call another code in another
context.


> It would break literally ALL existing code.

We simply convert Utility to [ThreadStatic]-variable.

> The need to pass context around is quite disturbing in my opinion...
> Every time you would like to create simple  Location or PExpr object
> you need to have ManagerClass at hand... Of course we could force
> users to do this and fix all code in nemerle sources, but the question
> is if it is really worth all the costs?

Static nature of compiler make many pain now and in the future (when the
compiler will be released). I vote on convert compiler for truly instance
base.