A Wasm function handle, it can be either a function from a host or an export from an Instance.
As it is only a handle to an object in Store, cloning is cheap
A host function ready to be used as an import for instantiating a module.
As it is only a handle to an object in Store, cloning is cheap.
A helper trait for creating a function with a static signature.
Should not be implemented by users.
Implemented for all functions that meet the following criteria:
* implement Send + Sync + ’static
* take or not take ImportCallContext as first parameter
* take from 0 to 16 i32 parameters
* return () or i32