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

Summary

In this chapter, you learned about the crucial technical skills and tools used in programming languages when they are reading the characters of program source code. Thanks to these skills, the rest of your programming language compiler or interpreter has a much smaller sequence of words/tokens to deal with, instead of the enormous number of characters that were in the source file. If we were successful, you will have taken away the following skills that you can use in your programming language or similar projects.

As input characters are read in, they are analyzed and grouped into lexemes. Lexemes are either discarded (in the case of comments and whitespace) or categorized for subsequent parsing purposes.

Besides categorizing lexemes, you learned to make tokens from them. A token is an object instance that is created for each lexeme when it is categorized. The token is a record of that lexeme, its category, and where it came from.

The lexemes' categories are the...