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 7

  1. Type checking finds many errors that would prevent the program from running correctly. But it also helps determine how much memory will be needed to hold variables, and exactly what instructions will be needed to perform the various operations in the program.
  2. A structure type is needed to represent arbitrarily deep composite structures, including recursive structures such as linked lists. Any given program only has a finite number of such types, so it would be possible to enumerate them and represent them using integer subscripts by placing them in a type table, but references to structures provide a more direct representation.
  3. If real compilers reported an OK line for every successful type check, non-toy programs would emit thousands of such checks on every compile, making it difficult to notice the occasional errors.
  4. Picky type checkers may be a pain for programmers, but they help avoid unintended type conversions that hide logic errors, and they also reduce...