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

Using Unicon's declarations and data types

You can't write a Unicon program without declaring things. Declaring something is the act of associating a name, visible within some scope and lifetime, with some chunk of code or memory capable of holding a value. Next, let's learn how different program components can be declared.

Declaring different kinds of program components

Unicon programs consist of one or more procedures beginning with main(). Program structure often also includes classes. Unicon distinguishes user-defined procedures from functions that are built into the language. The following patterns show the syntax structure for the primary declarations of bodies of code in Unicon's procedures and methods.

Declare procedure:

procedure X ( params ) [locals]* [initial] [exprs]* end

Declare method:

method X ( params ) [locals]* [initial] [exprs]* end

A procedure or method has a name, parameters, and a body ending with the word end. The body...