Summary
This chapter showed you how to write high-level operators and built-in functions for the runtime system of your language. One of the main points that you are to take away is that the implementation of operators and functions can range from completely different to almost entirely the same, depending on the language you are inventing.
The examples in this chapter taught you how to write code in your runtime system that will be called from generated code. You also learned how to decide when to make something a runtime function instead of just generating the code for it using instructions.
The next chapter will continue the topic of implementing built-in features by exploring domain control structures.
