[plt-scheme] Re: [Larceny-users] side effects in R6RS modules

On Tue, May 05, 2009 at 06:21:20PM +0300, Abdulaziz Ghuloum wrote:
> 
> On May 5, 2009, at 5:44 PM, Matthias Felleisen wrote:
> 
> >In PL, such questions should be decided via mathematical models that
> >do not depend on machines and compilers. That's the only way to truly
> >disambiguate the English in a spec.
> >
> >For whatever reasons, the editors moved the only piece of mathematics
> >semantics (which doesn't include modules and macros) to the appendix,
> >for reasons that still escape me. Well, they don't really. If you
> >don't have a tool for arbitrating two distinct interpretations of
> >an informal document, you can always claim that both are correct and
> >if you so desire, you can claim one of them is, eh, smart? :-)

Long ago, I chaired an ISO committee that issues a technical report to 
guide people devising programming language standards.  We recommended 
that a language definition include both formal (mathematical) and an 
informal (natural language) definitions.  The question came up which was 
to be authoritative in case of a conflict.  The recommendation was that, 
in case of a conflict, the language definition should be deemed to have 
an error;  said error should be resolved by whatever procedures would be 
invoked for any error in a standard.

Thus the double definition is to be taken as a matter of redundancy, so 
that typos and such would be unlikely to change the language.

-- hendrik