Programming in Lua

http://www.lua.org/pil/

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Programming in Lua

This is an online version of the first edition of the book

Programming in Lua
by Roberto Ierusalimschy
Lua.org, December 2003
ISBN 85-903798-1-7

The book is a detailed and authoritative introduction to all aspects of Lua programming, by Lua's chief architect. The first edition was aimed at Lua 5.0.

If you like the online version, please consider buying a copy of the second edition, which updates the text to Lua 5.1 and brings substantial new material.

For the official definition of the Lua language, see the reference manual.

Copyright © 2003-2004 Roberto Ierusalimschy. All rights reserved.
This online book is for personal use only. It cannot be copied to other web sites or further distributed in any form.

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Contents

Preface

Audience

Other Resources

A Few Typographical Conventions

About the Book

Acknowledgments

Part I. The Language

1 Getting Started

1.1 Chunks

1.2 Global Variables

1.3 Some Lexical Conventions

1.4 The Stand-Alone Interpreter

2 Types and Values

2.1 Nil

2.2 Booleans

2.3 Numbers

2.4 Strings

2.5 Tables

2.6 Functions

2.7 Userdata and Threads

3 Expressions

3.1 Arithmetic Operators

3.2 Relational Operators

3.3 Logical Operators

3.4 Concatenation

3.5 Precedence

3.6 Table Constructors

4 Statements

4.1 Assignment

4.2 Local Variables and Blocks

4.3 Control Structures

4.3.1 if then else

4.3.2 while

4.3.3 repeat

4.3.4 Numeric for

4.3.5 Generic for

4.4 break and return

5 Functions

5.1 Multiple Results

5.2 Variable Number of Arguments

5.3 Named Arguments

6 More about Functions

6.1 Closures

6.2 Non-Global Functions

6.3 Proper Tail Calls

7 Iterators and the Generic for

7.1 Iterators and Closures

7.2 The Semantics of the Generic for

7.3 Stateless Iterators

7.4 Iterators with Complex State

7.5 True Iterators

8 Compilation, Execution, and Errors

8.1 The require Function

8.2 C Packages

8.3 Errors

8.4 Error Handling and Exceptions

8.5 Error Messages and Tracebacks

9 Coroutines

9.1 Coroutine Basics

9.2 Pipes and Filters

9.3 Coroutines as Iterators

9.4 Non-Preemptive Multithreading

10 Complete Examples

10.1 Data Description

10.2 Markov Chain Algorithm

Part II. Tables and Objects

11 Data Structures

11.1 Arrays

11.2 Matrices and Multi-Dimensional Arrays

11.3 Linked Lists

11.4 Queues and Double Queues

11.5 Sets and Bags

11.6 String Buffers

12 Data Files and Persistence

12.1 Serialization

12.1.1 Saving Tables without Cycles

12.1.2 Saving Tables with Cycles

13 Metatables and Metamethods

13.1 Arithmetic Metamethods

13.2 Relational Metamethods

13.3 Library-Defined Metamethods

13.4 Table-Access Metamethods

13.4.1 The __index Metamethod

13.4.2 The __newindex Metamethod

13.4.3 Tables with Default Values

13.4.4 Tracking Table Accesses

13.4.5 Read-Only Tables

14 The Environment

14.1 Accessing Global Variables with Dynamic Names

14.2 Declaring Global Variables

14.3 Non-Global Environments

15 Packages

15.1 The Basic Approach

15.2 Privacy

15.3 Packages and Files

15.4 Using the Global Table

15.5 Other Facilities

16 Object-Oriented Programming

16.1 Classes

16.2 Inheritance

16.3 Multiple Inheritance

16.4 Privacy

16.5 The Single-Method Approach

17 Weak Tables

17.1 Memoize Functions

17.2 Object Attributes

17.3 Revisiting Tables with Default Values

Part III. The Standard Libraries

18 The Mathematical Library

19 The Table Library

19.1 Array Size

19.2 Insert and Remove

19.3 Sort

20 The String Library

20.1 Pattern-Matching Functions

20.2 Patterns

20.3 Captures

20.4 Tricks of the Trade

21 The I/O Library

21.1 The Simple I/O Model

21.2 The Complete I/O Model

21.2.1 A Small Performance Trick

21.2.2 Binary Files

21.3 Other Operations on Files

22 The Operating System Library

22.1 Date and Time

22.2 Other System Calls

23 The Debug Library

23.1 Introspective Facilities

23.1.1 Accessing Local Variables

23.1.2 Accessing Upvalues

23.2 Hooks

23.3 Profiles

Part IV. The C API

24 An Overview of the C API

24.1 A First Example

24.2 The Stack

24.2.1 Pushing Elements

24.2.2 Querying Elements

24.2.3 Other Stack Operations

24.3 Error Handling with the C API

24.3.1 Error Handling in Application Code

24.3.2 Error Handling in Library Code

25 Extending your Application

25.1 Table Manipulation

25.2 Calling Lua Functions

25.3 A Generic Call Function

26 Calling C from Lua

26.1 C Functions

26.2 C Libraries

27 Techniques for Writing C Functions

27.1 Array Manipulation

27.2 String Manipulation

27.3 Storing State in C Functions

27.3.1 The Registry

27.3.2 References

27.3.3 Upvalues

28 User-Defined Types in C

28.1 Userdata

28.2 Metatables

28.3 Object-Oriented Access

28.4 Array Access

28.5 Light Userdata

29 Managing Resources

29.1 A Directory Iterator

29.2 An XML Parser

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Last update: Wed May 9 11:40:44 BRT 2007