JVM Runtime Parametric Type Support

[John Rose]

On Jun 25, 2025, at 12:37 PM, Brian Goetz <brian.goetz at oracle.com> wrote:

 Note that the "side value" concept is essentially a way to upgrade Java's parameter-passing protocol to something more like Scala's implicits, where each method has two argument lists, one derived from types and one consisting of pure runtime values.  Compiler architects would love to have such a translation mechanism :)


True in general but the particulars might be a mismatch. Getting the implicit argument (just one) via an intrinsic call will dampen their ardor for the feature.

Meanwhile, indy gives about 10 other ways to get similar effects!

The real primitive here IMO is the ability to clone call trees at non-generic anchors, in a way that permits and encourages the VM to render them (when hot) as independently profiled and customized machine code. Also object layouts, but the code specialization is the super power.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/valhalla-spec-observers/attachments/20250625/311a1567/attachment.htm>