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

Running a Jzero program

At this point, we need to be able to test our bytecode interpreter, but we haven't presented the code generator that generates this bytecode yet! For this reason, most of the testing for this chapter's bytecode interpreter will have to wait until the next chapter, where we will present the code generator. For now, here is a hello world program. The source code is as follows:

public class hello {
   public static main(String argv[]) {
      System.out.println("hello");
   }
}

The corresponding Jzero bytecode might look something like this. One word is shown per line; the lines in hexadecimal show each byte as two hex digits. The opcode is in the leftmost byte, then the operand region byte, and then the operand in the remaining 6 bytes:

"Jzero!!\0"
"1.0\0\0\0\0\0"
0x0000040000000000
"hello\0\0\0"
0x0902380000000000     ...