RE: [sv-ec] inline constraints -- things are not really quite right yet (perhaps)

Johathan,

I agree that this is wouid be a useful capability in constraint. I
further
agree that it would be useful to be able to reference the pre-randomize
for any expression (not just simple random variables).

- Ray 

> -----Original Message-----
> From: Jonathan Bromley [mailto:jonathan.bromley@doulos.com] 
> Sent: Monday, November 12, 2007 8:39 AM
> To: Ryan, Ray; sv-ec@server.eda.org
> Subject: RE: [sv-ec] inline constraints -- things are not 
> really quite right yet (perhaps)
> 
> Ray,
> 
> [Jonathan]
> > > As a convenience feature, I would also suggest that
> > > *anything* with a local:: qualifier should be treated as a state 
> > > variable for the constraint, so that (as I suggested in 
> an earlier 
> > > post)
> > > 
> > >   c.randomize() with {x != local::c.x;};
> > > 
> > > would unambiguously mean "randomize c.x so that it gets a value 
> > > different from its present value".
> 
> [Ray]
> > This would be a nice convenience. However, it would be 
> better if this 
> > feature was also available in a regular constraint (inside 
> the class) 
> > rather than just in inline-constraints.
> 
> On reflection I completely agree that it would be a mistake 
> to confuse the name-resolution meaning of "local::" with this 
> treat-as-state behaviour.  Do you feel it's appropriate to 
> create a new Mantis proposing a system pseudo-function (maybe 
> $read_only(), to mimic the similar thing in 'e') for grabbing 
> the pre-randomization value of an expression for use as state 
> in a constraint?  Or should we put it to one side, because 
> there is too much else to do?  
> It's a feature that I sorely miss in SV constraints in 
> comparison with 'e'...
> --
> Jonathan Bromley, Consultant
> 
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