VM instruction implementation without huge switch()?

How would one go about making a virtual machine without using a huge and clumsy switch( opcode ) statement?

The architecture I'm implementing (DCPU-16) has about 35-40 different instructions.

First we familiarize ourselves with https://en.wikipedia.org/wiki/Visitor_pattern and refactor the bindings into container classes which would be dependently injected in polymorphic virtual functions using the https://en.wikipedia.org/wiki/Command_pattern encapsulated inside safe AbstractFactory methods.