Book Image

Build Your Own Programming Language

By : Clinton L. Jeffery
Book Image

Build Your Own Programming Language

By: Clinton L. Jeffery

Overview of this book

The need for different types of computer languages is growing rapidly and developers prefer creating domain-specific languages for solving specific application domain problems. Building your own programming language has its advantages. It can be your antidote to the ever-increasing size and complexity of software. In this book, you’ll start with implementing the frontend of a compiler for your language, including a lexical analyzer and parser. The book covers a series of traversals of syntax trees, culminating with code generation for a bytecode virtual machine. Moving ahead, you’ll learn how domain-specific language features are often best represented by operators and functions that are built into the language, rather than library functions. We’ll conclude with how to implement garbage collection, including reference counting and mark-and-sweep garbage collection. Throughout the book, Dr. Jeffery weaves in his experience of building the Unicon programming language to give better context to the concepts where relevant examples are provided in both Unicon and Java so that you can follow the code of your choice of either a very high-level language with advanced features, or a mainstream language. By the end of this book, you’ll be able to build and deploy your own domain-specific languages, capable of compiling and running programs.
Table of Contents (25 chapters)
1
Section 1: Programming Language Frontends
7
Section 2: Syntax Tree Traversals
13
Section 3: Code Generation and Runtime Systems
21
Section 4: Appendix

Checking method calls

The function call is the fundamental building block of both imperative and functional programming paradigms. In object-oriented languages, functions are called methods, but they can play all of the same roles that functions can. In addition to this, a set of methods provides an object's public interface. To type check a method call, both the number and the type of the parameters must be verified along with the return type.

Calculating the parameters and return type information

The type representation introduced in the previous Chapter 7, Checking Base Type, included a methodtype class that had fields for the parameters and the return type; however, we haven't yet presented the code to extract that information from the syntax tree and place it into the type. The parameters and return type of a method are called its signature. The grammar rule where a method signature is declared is the one that builds a MethodHeader node. To calculate the return...