Requiring weak purity for opAssign, postblit

[Jonathan M Davis]

On Saturday 25 December 2010 08:50:19 dsimcha wrote:
> == Quote from bearophile (bearophileHUGS at lycos.com)'s article
> 
> > dsimcha:
> > > Does anyone see a problem with requiring opAssign and postblits to be
> > > weakly pure to solve this problem?
> > 
> > Time ago I have even suggested contracts (pre/post/invariants) to be pure
> > (as
> 
> Design by Contract asks), or at least class invariants to be const on
> default.
> 
> > Bye,
> > bearophile
> 
> Yeah, this is a good idea iff we fix the template pure issue.

You can mark them as pure already. They're just not forced to be pure.

pure invariant()
{
  //This invariant is pure.
}


What would be really nice though is a version of writeln intended only for debug 
purposes which worked in pure functions. As I understand it, the main reason 
that invariants weren't pure in the first place was to allow for debug output, 
which can be extremely useful.

- Jonathan M Davis