Allow users to pass null as an optional argument

[GulgDev]

Currently, optional types only allow undefined. Is it possible to register an optional type that allows null as well as undefined?

[sbc100]

Can you elaborate a little more? Is this perhaps an issue with embind? Maybe the typescript bindings produced by emcc?

[GulgDev]

Bindings for std::optional only allow undefined to be passed from JS (passing null as an optional argument throws an error)