Don't use a mem reference for setting object fields

[Aidan63]

The mem reference erases the underlying type to just hx::Object*, this is a problem when you try and set a field of a function type in a host class from a script. Script closures and functions do not extend the new callable type so by using this type erased pointer is assigned a not callable object to a callable object pointer, which then causes memory errors when invoking it.

[tobil4sk]

Will this have an impact on performance?

[Aidan63]

Probably, the removed code means updating a field which contains an object will use runtime lookup.
A narrower fix would be to update the TypeData object to contain extra info if the object is a function (it already does this for array types), we could then use that to only opt out of the pointer method of the object field is for a function.
This work around is also only needed for host and script interactions, if it's purely script based then it's not needed, so there's probably further narrowing which could be done there (assuming it's possible to detect those cases).