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Contents at a Glance About the Author ..................................................................xiii About the Technical Reviewer ......................................................xv Acknowledgments ............................................................... xvii Introduction ......................................................................xix CHAPTER 1 Introduction to IronPython ...................................... 1 CHAPTER 2 IronPython Syntax ..............................................15 CHAPTER 3 Advanced IronPython ...........................................39 CHAPTER 4 IronPython Studio ............................................. 63 CHAPTER 5 Mixing and Mingling with the CLR ...............................79 CHAPTER 6 Advanced Development ...................................... 119 CHAPTER 7 Data Manipulation .............................................163 CHAPTER 8 Caught in a Web ............................................. 203 CHAPTER 9 IronPython Recipes ............................................239 INDEX ...................................................................... 277 v Contents About the Author ..................................................................xiii About the Technical Reviewer ......................................................xv Acknowledgments ............................................................... xvii Introduction ......................................................................xix CHAPTER 1 Introduction to IronPython ................................. 1 A Humble Beginning ............................................. 1 Jython: A Taste for Java ...........................................2 IronPython: “Import .NET” ........................................ 2 Why Is .NET Important? .......................................... 3 What Exactly Is IronPython? ........................................3 What Can IronPython Do for Me Today? ............................ 4 Yes, But Will It Blend? .............................................5 What Is a Dynamic Language? .................................... 6 What This Will Book Cover .........................................8 Who This Book Is For ............................................ 9 For Consenting Adults Only! ........................................9 Prerequisites ....................................................10 IPY and You .....................................................12 Summary .......................................................14 CHAPTER 2 IronPython Syntax ......................................... 15 Data Types and Control Structures .................................15 Strings .........................................................15 Integers ....................................................... 17 Conditional Statements ...........................................19 Input() or Raw_Input() ............................................20 Error Handling and Exceptions ................................... 21 Try-Catch-Finally ................................................23 vii viii ■CONTENTS Built-In Functions ................................................26 abs ...................................................... 26 chr. 26 dict ...................................................... 27 dir ....................................................... 27 Files via open ............................................. 28 for (iterations) ..............................................29 help .......................................................30 hex ...................................................... 30 int ....................................................... 31 len ........................................................32 list ........................................................32 max and min ...............................................32 ord ...................................................... 33 pow .......................................................33 random ....................................................34 randrange ................................................ 35 round .................................................... 36 uniform .................................................. 37 But Wait, There’s More! ......................................... 37 Summary .......................................................38 CHAPTER 3 Advanced IronPython ...................................... 39 String Operations Revisited ...................................... 39 A Quick Software Development Detour ............................ 43 Back on Track ................................................. 44 Floating-Point Numbers ......................................... 46 Booleans ...................................................... 48 Classes and OOP ............................................... 48 .NET Data Types. 59 Value and Reference Types ...................................... 60 Mixing and Matching .............................................61 Summary .......................................................62 ■CONTENTS ix CHAPTER 4 IronPython Studio ...........................................63 Hopping Onto the Steamroller .....................................63 So Much Typing...Is There a Better Way? ..........................66 Forms, from the Ground Up .......................................70 It’s All This Substandard Wiring! ...................................72 Clean Code Is Happy Code ........................................74 Summary .......................................................78 CHAPTER 5 Mixing and Mingling with the CLR .........................79 “CLR-ance, Clarence.” ...........................................79 The Plan ...................................................... 80 The Design .................................................... 81 The Implementation ............................................ 82 Bad Medicine .................................................. 91 I’d Like to See a Menu .......................................... 97 Reading, Writing, Arithmetic ..................................... 99 Open Sesame ..................................................101 I Can’t Even Save Myself ....................................... 106 Print, Please .................................................. 110 A Touch of OOP ............................................... 112 Exit Strategy ...................................................116 Beautification ................................................. 116 Project Postmortem .............................................117 Summary ......................................................118 CHAPTER 6 Advanced Development ....................................119 Base Classes for Fun and Profit (aka “The LEGOs on the Bottom Don’t Really Exist”) ...........................................119 Plug and Play ................................................. 130 Architecting Flexibility ...........................................131