> On 29 Mar 2019, at 14:24, Ben Coman <[email protected]> wrote:
>
>
>
> On Fri, 29 Mar 2019 at 18:57, Tim Mackinnon <[email protected]> wrote:
> Hi Peter - yes of course you are right that its malleable, I guess I’m often
> suprised about the things we leave out and then discover weird things we’ve
> put in.
>
> I had a quick look at LinkedList (I should have thought of that) - I might be
> able to do something with that (and this is now more out of curiosity) - but
> gosh its an easy way to crash your image. Having linked the first to the
> last, and then tried a quick: list after: $n - I’m now guessing I’m stuck in
> an infinite loop that even Cmd . won’t break out of!!!! ouch.
>
> If you look at Hier(archy) of LinkList you'll see Semaphore underneath it.
> I'm not sure, but there may be some VM magic around Semaphore and Process
> management that makes it fragile to changes.
> I believe there have been some proposals to separate out the Process related
> LinkedList stuff, but I can't remember the exact arguments.
Yes, we did that… there is now ProcessList.
We ran into that problem far too often “hey, LinkedList can be cleaned up
easily like this!” —> boom, everything broken.
Now we have ProcessList where it matters if code is changed to introduce a
message send more and LinkedList where it does not.
Marcus
