Re: Correction to my last posting Re: dependent and independent intervals, proposal to toss out text2interval. Was re: about emp (was: Motion 42:no)
On 2013-03-05 07:39:21 -0600, Ralph Baker Kearfott wrote:
> Sorry, I meant to say "would NOT cause the implementation
> to not be standard conforming".
>
> Please excuse me if I have not been attentive
> enough to this discussion to grasp it fully.
> However, regarding extensions, isn't it
> true that something an implementation provides
> that is not explicitly required in the standard
> does not impact whether or not that implementation
> is standard-conforming unless the standard
> explicitly prohibits it? For example,
> suppose an implementer of a P-1788 conforming
> system specifies that the implementation also contain
> functions supporting quaternion arithmetic. Since
> P-1788 does not explicitly prohibit quaternion
> arithmetic, the existence of quaternion arithmetic
> bundled with the implementation would cause the
> implementation to not be standard conforming,
> n'est pas?
Quaternion arithmetic would be completely out of the scope of
the standard. Here, the behavior of text2interval is involved.
For instance, if the standard says that the implementation
shall return an error on any string that is not in the specified
format, any extension would be forbidden. A different function
may not be satisfactory. For instance, a user may just need
something like
text2interval(interval2text(x)) contains x
without knowing whether extensions are used internally.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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