Separation between MemorySegment and MemoryScope

[Remi Forax]

Hi all,
I've taken a look to the doc about the separation between MemorySegment/MemoryScope (the branch panama-foreign is still building ...)

I like this change it makes things conceptually cleaner, in my case being able to close several segments at the same time,
but at the same time i'm still mourning the fact that before this change, i really liked the fact that a MemorySegment was confined to a thread by default.

Thinking a little more about that, I wonder if having a default behavior with respect to the MemoryScope is a good idea,
i wonder if it is not better to go full explicit, i.e. to have the methods that creates a MemorySegment to always take the scope as last parameter.
It forces us users to think in term of scope instead of using a default which may not be a good one depending on the application/library.

It has also the advantage to cut the number of methods by half, which is a huge bonus because it keeps the things simple.


Another question, at some point, i would like to use a MemorySegment with the Vector API* and i would be very cool if there was a way to deactivate the bound checks only for some MemorySegments, not all.
Given we have ofNativeRestricted, i wonder if having a noBoundChecks for a particular MemoryScope (composable with the rest) with the same restriction (the property foreign.restricted has to be set) is something possible or not.

regards,
Rémi

* currently i'm using a ByteBuffer (from MemorySegment.asByteBuffer()) but i've hard time to have the JIT to remove the bound checks, it seems that the fact that an index is < buffer.capacity() has no effect on the generated code (perhaps it's because the fields of ByteBuffer are not tagged with @Stable ?).