Re: Constructors motion 30 Version 2: small amendment
On 2012-02-07 11:35:09 +0000, John Pryce wrote:
> ======================================================================
> The standard shall specify constructors at Level 1 as described below.
> ======================================================================
[...]
> A NaI by definition is a decorated interval value that can never be
> the result of a successful construction, and is used to signal a
> construction failure. What NaI values exist will be decided by a
> later motion on decorations, but there must be at least one.
Isn't NaI a Level 2+ notion only?
> The decorated interval constructors nums2interval(l,u),
> num2interval(x), text2interval(t), empty(), entire() are defined as
> follows. If the value xx of the corresponding bare interval
> constructor is defined, then the decorated interval constructor is
> said to succeed, and returns (xx,d) where d is appropriate, in the
> decoration system, for a new interval with the value xx. Otherwise
> it fails, and returns a NaI as determined by the decoration system.
Ditto.
I think that like for bare versions, you should just say that the
result is undefined.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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