I'm fine with that change. For me, it's more where you put the emphasis - how it behaves on stack, it behavse like a primitive type ,the "pass by value" Dan is talking about - how it behaves on heap, it behaves by inlining itdelf in its container.
So they are a primitive inlining class :) Rémi > De: "Brian Goetz" <brian.go...@oracle.com> > À: "daniel smith" <daniel.sm...@oracle.com>, "valhalla-spec-experts" > <valhalla-spec-experts@openjdk.java.net> > Envoyé: Lundi 5 Octobre 2020 21:22:15 > Objet: Re: Terminology update: primitive objects > There's always been a duality between whether inline classes are "faster > objects" or "user-programmable primitives." Until now, we're been erring on > the > "faster objects" side of the line, but after some thought, we think that > flipping the perspective will better frame what these new features are for. > The obvious stumble you have to get over before this idea is appealing is "but > these are not primitives." So we have to be explicit about that. But, once you > buy that, I think these terms work much better. > On 10/5/2020 3:18 PM, Dan Smith wrote: >> We've been struggling with some uncomfortable rough edges of the "inline >> class"/"inline type" terminology for awhile. After multiple rounds of >> bikeshedding, here's an alternative that the Oracle team feels pretty good >> about: >> - A *primitive object* is a new kind of object that lacks identity. It has >> special behavior with respect to equality, synchronization, and related >> operations. *Identity object* describes all other objects (including arrays). >> (The new objects are "primitive" in the sense that they are lighter-weight >> and >> represent simple, immutable values.) >> - A *primitive class* (formerly *inline class*) is a special class whose >> instances are primitive objects. Primitive classes are always concrete and >> final, and their declarations are subject to various restrictions. A class >> that >> is not primitive is either an *identity class* or an *abstract class* (or >> Object, if we don't end up making it abstract). >> - A *primitive value type* (formerly *inline type*) is a type whose values >> are >> primitive objects—the objects themselves, not *references* to the objects. >> Each >> primitive class has a primitive value type, typically denoted by the class >> name. >> - A *primitive reference type* is a type whose values are references to >> primitive objects, or null. Each primitive class has a primitive reference >> type, typically denoted as ClassName.ref. >> - The general term *primitive type* refers to either a primitive value type >> or a >> primitive reference type. The general term *reference type* continues to >> mean a >> type whose values are reference to objects (of unspecified kind), or null. >> - In the Java language, the existing primitive values will become primitive >> objects, with java.lang.Integer, etc., acting as their primitive classes. >> When >> needed, *built-in primitive value type*, etc., can be used to refer to their >> types. In the JVM, something like *primitive object type* might be >> appropriate >> to distinguish between primitive objects and the built-in numerics. >> The type terminology leans on intuitions about "pass by value" and "pass by >> reference". Some languages pass *variables* by value or reference, but in >> Java >> the, er, primitive, is passing *objects* by value or by reference. Similar >> properties apply in both contexts. >> --- >> This is a brief sketch, just enough to define the terms. Future documents, >> including project overviews, JEPs, and specs, will illustrate use of the >> terms >> in the broader context of the language and VM.
