New candidate JEP: 335: Deprecate the Nashorn JavaScript Engine

[Paulo Lopes]

Hi all,

I'll try to join the thread now. I'm the "core" developer of JS support
of Eclipse Vert.x and Nashorn is the key component to get this support.
Recently I've been working on getting both Nashorn and Graal working on
the same code base and I've observed that Graal isn't quite there yet.

Just to name a couple of things Graal support for multithreaded code is
not available in scripting mode, and is in Nashorn; dynalink allows
definining custom type casts that are used by Nashorn when crossing
language boundaries (this is quite nice as it reduces the boilerplate
code at the scripting side, thus not having it, kind of defeats the
point of scripting for the convenience using a script as lots of
boilerplate needs to be added).

So in a nutshell, removing Nashorn without having a proper stable
alternative (be it project Detroit V8) or a fully functional GraalVM.js
should not be done without having some leeway time to projects to adapt
to the alternatives.

Just my 2cts,

Paulo