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Re: [Scheme-reports] Comments on draft 6

Andy Wingo writes:

> On Fri 24 Feb 2012 06:40, John Cowan writes:
> > What I'd like to do is to drop this language altogether and just
> > say (as we already do) that it's an error to set an undefined
> > identifier.  Then we can add a note saying that some
> > implementations extend the standard by automatically defining any
> > undefined identifier before setting it.  This language belongs
> > with `set!`.
> If it were only this simple, sure.  But this distinction between
> unbound and bound affects introduced toplevel macro bindings.  If
> the identifier is really unbound, the introduced identifier should
> be given a fresh name.  If not, not.
> It's a very ugly corner of the language.

Implementations can do anything they like when the report says "it is
an error".

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