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

Marking live data and sweeping the rest

This section gives an overview of the Unicon garbage collector, which is a mark-and-sweep style of garbage collector that was developed for the Icon language and then extended. It is written in (an extended dialect of) C, like the rest of the Icon and Unicon runtime system. Since Unicon inherited this garbage collector from Icon, much of what you see here is due to that language. Other aspects of this garbage collector are described in the book, The Implementation of Icon and Unicon: a Compendium.

In almost all garbage collectors other than reference counting, the approach is to find all the live pointers that are reachable from all the variables in the program; everything else in the heap is garbage. In a mark-and-sweep collector, live data is marked when it is found, and then all the live data is moved up to the top of the heap, leaving a big, beautiful pool of newly available memory at the bottom. The collect() C function from Unicon&apos...