That would mean that redefining a type of which there are any (reachable) instances would invalidate the entire system. That seems significantly worse than simply not allowing types to be redefined without restarting. One could potentially make references to "invalidated" objects #undef, but that seems likely to leave the object graph in a completely unusable state.
On Thu, Feb 4, 2016 at 6:11 PM, Michael Landis <[email protected]> wrote: > They would be invalid too. I know... no garbage collector, so it would be > necessary to find the inbound references. Smart pointers maybe? Yet > another performance hit. > > On Thursday, February 4, 2016 at 1:54:24 PM UTC-8, Stefan Karpinski wrote: >> >> How does one "release" an object? What happens to other objects that >> retain references to those objects? >> >> On Thu, Feb 4, 2016 at 4:35 PM, Michael Landis <[email protected]> >> wrote: >> >>> if you added a field, the existing objects could still be valid. If you >>> killed an attribute, they are invalid and can be released. >>> >>> On Thursday, February 4, 2016 at 10:55:25 AM UTC-8, Stefan Karpinski >>> wrote: >>>> >>>> What happens to existing objects of a type when you redefine the type? >>>> >>>> On Thu, Feb 4, 2016 at 1:46 PM, Michael Landis <[email protected]> >>>> wrote: >>>> >>>>> I think it would be nice to be able to undefine a type, so restarting >>>>> the environment is not required when adding or deleting an attribute from >>>>> a >>>>> type description. Not being able to update a type definition without >>>>> restarting the environment is a royal pain in the ass. >>>>> >>>>> >>>>> On Saturday, March 8, 2014 at 9:55:37 AM UTC-8, Freddy Chua wrote: >>>>>> >>>>>> Suppose I have a Type >>>>>> >>>>>> type Foo >>>>>> a >>>>>> b >>>>>> end >>>>>> >>>>>> f = Foo(1,2) >>>>>> f.a = 1 >>>>>> f.b = 2 >>>>>> >>>>>> how do I test whether f.a is defined >>>>>> I do this isdefined(f, 1) but isdefined(f, 'a') does not work >>>>>> >>>>>> another question >>>>>> how do i undefine f.a such that isdefined(f,1) now returns false >>>>>> >>>>> >>>> >>
