[r6rs-discuss] [Formal] Allow compilers to reject obvious violations

[Matthias Felleisen]

>     Implementations may reject a library or program
>     prior to execution if they can establish that
>     (1) some definition or expression within the
>     library or program would inevitably raise a
>     &violation exception were it ever to be executed,
>     and (2) the exception would be raised without
>     calling any of the following procedures: error,
>     assertion-violation, raise, raise-continuable.

[Apologies if my reply violates any formal requirements.]

  1. When an implementation is allowed to reject a program without  
running it,
     it comes with a filter also known as a type system.

  2. Naturally I don't reject type systems per se but I think that a  
serious
     language definition shouldn't introduce such systems without  
specifying
     them. Otherwise a language/implementation will appear whimsical to
     programmers.

-- Matthias