Re: non-consecutive ranges

[dennison@telepath.com]

In article <7gct90$7hr$1@nnrp1.dejanews.com>,
  vlight@my-dejanews.com wrote:
>
>
> is there a way to define a variable to have a non-consecutive range?  for
> instance, let's say i wanted to define variable X with a range from 2 to 1024
> and 4096 to 8192.
>
>   X : Integer range (1 .. 1024) and (4096 .. 8192);
>
> or something similar to this declaration.  in addition to define
> non-consecutive ranges, could i define a range of odd numbers? even numbers?
>
> how would i go about declaring this?

There is no language mechanism for inserting "holes" in numeric types.

Enumerations with rep clauses can be used to skip over certian actual values
(although conceptually there are no "holes" in the enumeration itself). But
trying to define an "Odd" type by enumerating every odd integer would be
beyond painful.

Another possibilty would be to declare a controlled type, and write
initialization and all the mathematical and conversion operations you need to
ensure that Constraint_Error is raised if the number ever goes even.

A third possibility is to bag it and move on...

--
T.E.D.

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