Pro DLR in .NET 4

314 Pages·2010·5.216 MB·English

by  Chaur Wu (auth.)

Pro DLR in .NET 4

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Chaur Wu
Pro DLR in .NET 4
Copyright © 2010 by Chaur Wu
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I want to dedicate this book to Sarah, Everett, Cedric, and Chiachi
(cid:3) CONTENTS AT A GLANCE
Contents at a Glance
(cid:3) About the Author..................................................................................................xiv
(cid:3) About the Technical Reviewer..............................................................................xv
(cid:3) Acknowledgments...............................................................................................xvi
(cid:3) Introduction........................................................................................................xvii
PART 1 (cid:3) (cid:3) (cid:3) DLR Fundamentals............................................................................1
(cid:3) Chapter 1: Introduction to DLR...............................................................................3
(cid:3) Chapter 2: DLR Expression....................................................................................27
(cid:3) Chapter 3: Late Binding and Caching....................................................................65
(cid:3) Chapter 4: Late Binding and Interoperability........................................................87
(cid:3) Chapter 5: Dynamic Objects................................................................................109
(cid:3) Chapter 6: DLR Hosting API.................................................................................133
PART 2 (cid:3) (cid:3) (cid:3) Applying the DLR...........................................................................163
(cid:3) Chapter 7: DLR and Aspect-Oriented Programming...........................................165
(cid:3) Chapter 8: Metaprogramming.............................................................................185
(cid:3) Chapter 9: Stitch — A DSL for Hosting Languages.............................................211
(cid:3) Chapter 10: Application Scripting.......................................................................239
(cid:3) Chapter 11: DLR in Silverlight.............................................................................251
(cid:3) Chapter 12: Dynamic Languages on JVM...........................................................275
(cid:3) Index...................................................................................................................297

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(cid:3) CONTENTS
Contents
(cid:3) About the Author..................................................................................................xiv
(cid:3) About the Technical Reviewer..............................................................................xv
(cid:3) Acknowledgments...............................................................................................xvi
(cid:3) Introduction........................................................................................................xvii
PART 1 (cid:3) (cid:3) (cid:3) DLR Fundamentals............................................................................1
(cid:3) Chapter 1: Introduction to DLR...............................................................................3
Setting Up Code Examples.................................................................................................4

Software Requirements............................................................................................................................4

Installing the DLR, IronPython, and IronRuby...........................................................................................5
Hello World Examples........................................................................................................6

Implementing REPL for the Hello Language.............................................................................................9
Practical Uses for the DLR.................................................................................................9

Application Scripting and DSL................................................................................................................10

XML Builder............................................................................................................................................10

Aspect-Oriented Programming...............................................................................................................11
Runtime...........................................................................................................................13

Runtime vs. Run Time.............................................................................................................................14

Run Time vs. Compile Time....................................................................................................................14
Dynamic vs. Static...........................................................................................................16

Dynamic Typing......................................................................................................................................17

Dynamic Dispatch...................................................................................................................................20
Language.........................................................................................................................21
Programming Languages in Practice...............................................................................22
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Putting It Together...........................................................................................................24
Summary.........................................................................................................................25
(cid:3) Chapter 2: DLR Expression....................................................................................27
DLR Expression as a Language........................................................................................27

Code as Data..........................................................................................................................................28

A Common Denominator like CLR...........................................................................................................28

Concrete Syntax and Serialization..........................................................................................................29
Expressions vs. Statements.............................................................................................29
Expression Type and Kind................................................................................................31
Binary Expressions..........................................................................................................33
Flow Control Expressions................................................................................................36

If-Then-Else Expressions........................................................................................................................37

Switch Expressions................................................................................................................................38
Scopes and Name Binding...............................................................................................39

Lexical vs. Dynamic Scope.....................................................................................................................40

BlockExpression and Lexical Scoping....................................................................................................41
Lambda Expressions and Closure....................................................................................44
The GotoExpression Class................................................................................................46
While Loops.....................................................................................................................48
Dynamic Expressions.......................................................................................................49
Index Expressions............................................................................................................52
Expression Abstraction, Reduction and Extension...........................................................53
Immutability and the Visitor Pattern................................................................................55

Visitor Pattern in General........................................................................................................................56

Visitor Pattern in DLR Expression...........................................................................................................57

Expression Visitor Examples...................................................................................................................59
Summary.........................................................................................................................63
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(cid:3) Chapter 3: Late Binding and Caching....................................................................65
Binding.............................................................................................................................65
Call Sites and Early Binding.............................................................................................66
Call Sites and Late Binding..............................................................................................67
DLR Binders.....................................................................................................................68
Set Up Code Examples.....................................................................................................69

Making a Debug Build of the DLR for .NET 2.0.......................................................................................69

Developing for Both .NET 2.0 and .NET 4.0............................................................................................69
The CallSiteBinder Class..................................................................................................71
DLR Call Sites..................................................................................................................72
Binding Restrictions and Rules........................................................................................73
Checking Binding Rules in Debug Mode..........................................................................75
Caching............................................................................................................................78

Three Cache Levels................................................................................................................................78

Late-Binding Context..............................................................................................................................80

L0 Cache Example..................................................................................................................................82

L1 Cache Example..................................................................................................................................83

L2 Cache Example..................................................................................................................................84
Creating Canonical Binders.............................................................................................86
Summary.........................................................................................................................86
(cid:3) Chapter 4: Late Binding and Interoperability........................................................87
Language Interoperability................................................................................................87
Static and Dynamic Objects.............................................................................................91
Late-Binding Logic in Two Places....................................................................................92

Late Binding Logic in Binders.................................................................................................................92

Late-Binding Logic in Dynamic Objects..................................................................................................94
Late-Bound Actions.........................................................................................................94
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Examples................................................................................................................................................94

Common Type System............................................................................................................................96

Class Hierarchy of Binders.....................................................................................................................99
Implement a Custom Binder Class.................................................................................100
Interoperability Protocol................................................................................................102
Summary.......................................................................................................................106
(cid:3) Chapter 5: Dynamic Objects................................................................................109
What is a Dynamic Object?............................................................................................109
IDynamicMetaObjectProvider Interface.........................................................................111
Dynamic Meta Objects...................................................................................................112

DynamicMetaObject and Binding Logic................................................................................................113

DynamicMetaObject and Binding Result..............................................................................................114
Interoperability...............................................................................................................115
DynamicObject Class.....................................................................................................119
XML Builder...................................................................................................................122
Summary.......................................................................................................................130
(cid:3) Chapter 6: DLR Hosting API.................................................................................133
Life Without the DLR Hosting API...................................................................................133

Using a Static Language’s Code in Another Static Language...............................................................134

Using a Static Language’s Code in a Dynamic Language.....................................................................134

Using a Dynamic Language’s Code in a Static Language.....................................................................135

Using a Dynamic Language’s Code in Another Dynamic Language.....................................................136
Overview of the DLR Hosting API...................................................................................136

Major Classes in the API.......................................................................................................................137

The Tale of Two APIs............................................................................................................................138

The DLR Hosting API in Relation to Binders and Dynamic Objects.......................................................139
Using Script Runtime to Execute Code..........................................................................139
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Configuring the Languages You Want to Speak.............................................................140

Configuring Script Runtime Declaratively.............................................................................................141

Configuring Script Runtime Programmatically.....................................................................................142
Scripting an Object Model.............................................................................................143
Script Scopes.................................................................................................................145
Value and Reference Variables......................................................................................146

Global Scope and Variable Passing......................................................................................................147

Language Neutral Scope and Variable Passing....................................................................................148
Level Two Use of the DLR Hosting API...........................................................................150

Compiling Code.....................................................................................................................................150

Loading Assemblies into Script Runtime..............................................................................................152

Creating Python Class Instances Using Object Operations...................................................................153
Level Three Use of the DLR Hosting API........................................................................154

Script Host............................................................................................................................................154

Object Operations.................................................................................................................................156

Remote Script Runtime........................................................................................................................156
.NET Remoting Quick Tour.............................................................................................158
Running Script Runtime in a Separate Process.............................................................159
Summary.......................................................................................................................161
PART 2 (cid:3) (cid:3) (cid:3) Applying the DLR...........................................................................163
(cid:3) Chapter 7: DLR and Aspect-Oriented Programming...........................................165
Aspect-Oriented Programming......................................................................................165

Cross-Cutting Concerns........................................................................................................................165

Advice, Join Points, and Pointcuts.......................................................................................................166

An Example...........................................................................................................................................167

A Test Run............................................................................................................................................170
AOP for Dynamic Objects...............................................................................................171

Understanding the Framework.............................................................................................................171
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Implementing the Framework..............................................................................................................172
Integration with Spring.NET AOP...................................................................................174

Getting the AOP Advisors......................................................................................................................175

Implementing Advice............................................................................................................................177

Applying Advice....................................................................................................................................178

Cutting Across Dynamic and Static Objects.........................................................................................180
Summary.......................................................................................................................183
(cid:3) Chapter 8: Metaprogramming.............................................................................185
Overview of Metaprogramming.....................................................................................185
Changing Class Definitions............................................................................................186

Ruby.....................................................................................................................................................187

Python...................................................................................................................................................189

DLR.......................................................................................................................................................191
LINQ Query Provider.......................................................................................................196

Understanding the End Goal.................................................................................................................196

Implementing the Query Class..............................................................................................................196

Implementing the QueryProvider Class................................................................................................198

Implementing QueryExpressionVisitor..................................................................................................200
Data Access...................................................................................................................201

Static Data Access................................................................................................................................202

Dynamic Data Access...........................................................................................................................204

Generated Data Access........................................................................................................................206
Summary.......................................................................................................................210
(cid:3) Chapter 9: Stitch — A DSL for Hosting Languages.............................................211
The Need for Stitch........................................................................................................211
Syntax of the Stitch Language.......................................................................................212
Requirements for the Example......................................................................................214

Software Requirements........................................................................................................................214
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