On Thu, Oct 31, 2013 at 10:10:03PM +0100, Timon Gehr wrote: > On 10/31/2013 09:05 PM, H. S. Teoh wrote: [...] > >So, in a nutshell, my proposal is: > > > >- Functions that, besides invoking a delegate parameter, are pure, > > should be allowed to be marked as pure. > > > >- Template functions that, besides invoking a delegate parameter, > > perform no impure operations should be inferred as pure. > > > >- A function that takes a delegate parameter cannot be strongly pure > > (but can be weakly pure), unless the delegate itself is pure. > > Should probably be 'pure immutable', as lined out above. Do you agree? [...]
Yes, you're right. If the delegate can't modify anything externally, then the function can be made strongly pure. T -- One reason that few people are aware there are programs running the internet is that they never crash in any significant way: the free software underlying the internet is reliable to the point of invisibility. -- Glyn Moody, from the article "Giving it all away"
