func helloName(_ js.Value, args []js.Value) (interface{}, error) {
	return fmt.Sprintf("Hello, %s!", args[0].String()), nil
}
helloName's first value is JavaScript's `this`.
However, the way that the JS bridge is written, it will always be JavaScript's undefined.

If returning a non-nil error value, the resulting promise will be rejected by API consumers.
The rejected value will JavaScript's Error, with the message being the go error's message.

See other examples which use the Go WASM bridge api, which show more flexibility and type safety when interacting
with JavaScript.
package main
import (
	"fmt"
	"syscall/js"
)
const hello = "Hello!"