Programming in Lua, Fourth Edition Roberto Ierusalimschy Copyright © 2016, 2003 Roberto Ierusalimschy Feisty Duck Digital Book Distribution www.feistyduck.com Licensed for the exclusive use of: Eric Taylor <jdslkgjf.iapgjflksfg@yandex.com> Contents About the Book ................................................................................................................. ix I. The Basics ...................................................................................................................... 1 1. Getting Started ........................................................................................................ 4 Chunks .............................................................................................................. 4 Some Lexical Conventions ................................................................................... 6 Global Variables ................................................................................................. 7 Types and Values ................................................................................................ 7 Nil ............................................................................................................ 8 Booleans .................................................................................................... 8 The Stand-Alone Interpreter .................................................................................. 9 2. Interlude: The Eight-Queen Puzzle ............................................................................ 12 3. Numbers ............................................................................................................... 15 Numerals .......................................................................................................... 15 Arithmetic Operators .......................................................................................... 16 Relational Operators .......................................................................................... 17 The Mathematical Library ................................................................................... 18 Random-number generator .......................................................................... 18 Rounding functions .................................................................................... 18 Representation Limits ......................................................................................... 19 Conversions ...................................................................................................... 21 Precedence ....................................................................................................... 22 Lua Before Integers ........................................................................................... 22 4. Strings ................................................................................................................. 24 Literal strings .................................................................................................... 24 Long strings ..................................................................................................... 25 Coercions ......................................................................................................... 26 The String Library ............................................................................................. 27 Unicode ........................................................................................................... 29 5. Tables .................................................................................................................. 33 Table Indices .................................................................................................... 33 Table Constructors ............................................................................................. 35 Arrays, Lists, and Sequences ............................................................................... 36 Table Traversal ................................................................................................. 38 Safe Navigation ................................................................................................. 38 The Table Library ............................................................................................. 39 6. Functions .............................................................................................................. 42