LRU cache for ~=

[Andrei Alexandrescu]

Bill Baxter wrote:
> On Mon, Oct 19, 2009 at 5:07 PM, Andrei Alexandrescu
> <SeeWebsiteForEmail at erdani.org> wrote:
>> Rainer Deyke wrote:
>>> Andrei Alexandrescu wrote:
>>>> One surprising (but safe) behavior that remains with slices is this:
>>>>
>>>> void fun(int[] a) {
>>>>   a[0] = 0;
>>>>   a ~= 42;
>>>>   a[0] = 42;
>>>> }
>>>>
>>>> The caller may or may not see 42 in the first slot after the call.
>>> Your definition of "safe" is clearly not aligned with mine.
>>>
>>>
>> What's yours?
> 
> Probably something like "safe from easy-to-write hard-to-debug
> programming errors".
> 
> I agree that it would stink if all these changes were made and *still*
> one of the top gotchas with arrays/slices remained.  It also makes me
> think slices and appending just don't belong together.  Appending to a
> view ... just say no.

How to reconcile this viewpoint with that of people who find ~= all too 
darn convenient?

Andrei