RE: EXTERNAL: Re: [vhdl-200x] Modular types

From: <>
Date: Wed Jul 02 2014 - 18:11:20 PDT
On Wednesday, July 02, 2014 10:11 AM, Brent Hayhoe wrote:
> It feels like we're so close to being able to implement them now and generate
> a package of overloaded subprograms.

Several people have pointed out that direct assignment remains a problem even
if you overload the arithmetic operators appropriately.  That's why Andy
suggested generalizing resolution functions as a hook into the assignment

> We can then create a function to return the modulus of the subtype using:
>     'subtype'high - 'subtype'low + 1
> or rather we can't at present because we can't get this from the actual part
> of the interface element.

Is there a technical reason for this?  (Compiler people?)  I know entity
interface array objects can take their index and element ranges from actuals.
It seems natural for an unconstrained integer or other discrete type to take
its range from the actual.  In fact, it seemed natural enough that I wrote a test case to confirm that these attributes *don't* pass through the interface.  This seems like it would cause problems if an out-mode actual object has a(n integer) range constraint and the procedure starts manipulating it.  I guess I don't do this much in practice, but I can certainly imagine it being a problem.

- Ryan

This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
Received on Wed Jul 2 18:11:46 2014

This archive was generated by hypermail 2.1.8 : Wed Jul 02 2014 - 18:12:23 PDT