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

Chapter 5: Syntax Trees

The parser we constructed in the last chapter can detect and report syntax errors, which is a big, important job. When there is no syntax error, you need to build a data structure during parsing that represents the whole program logically. This data structure is based on how the different tokens and larger pieces of the program are grouped together. A syntax tree is a tree data structure that records the branching structure of the grammar rules used by the parsing algorithm to check the syntax of an input source file. A branch occurs whenever two or more symbols are grouped together on the right-hand side of a grammar rule to build a non-terminal symbol. This chapter will show you how to build syntax trees, which are the central data structure for your programming language implementation.

This chapter covers the following main topics:

  • Learning about trees
  • Creating leaves from terminal symbols
  • Building internal nodes from production rules
  • ...