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Re: [Scheme-reports] multiple values module

On Sat, 21 May 2011, John Cowan wrote:

> Eli Barzilay scripsit:
>>> Examine HTML5 and ECMAScript 5 for yourself; the above description
>>> is trivially false about them.
>> You mean that these standards don't leave >>anything<< up to
>> implementations?
> That is, at least, the goal of the standards and the intention of the
> people who write them.  Ambiguity may of course be lurking somewhere in
> the text, but when found it is removed by corrigendum.

I prefer William Clinger's philosophy regarding standards, which can be
found somewhere in the R6RS discussions.  From memory, a standard posits
a set of postulates that can be used to infer a set of portable programs.
Not all programs allowed by an implementation need to be portable, but if
the set of postulates is simple enough, it should be relatively easy to 
program in the portable sublanguage.

In this approach, a standard does not need to specify everything.  In 
particular, it should not need to specify things that are not useful to many 
implementors and programmers.  Specifying that an unspecified value be
returned by a command is a prime example of a a postulate that does not need to 
be added to the language specification.

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