Contents

• 0. Preface
• 0.1. Acknowledgments
• 1. Command Line Arguments
• 1.1. A New Approach
• 1.2. Flexibility
• 1.3. Various Options
• 1.4. A Critical Attitude
• 1.5. An Overview
• 1.6. A Beautiful Violation
• 1.7. Arguments about Arguments
• 2. Encapsulating Information
• 2.1. A Soft Violation
• 2.2. Four Occurrences
• 2.3. Danger
• 2.4. A Matter of Principle
• 2.5. An Option Block
• 2.6. Growing a Manual
• 2.7. An Full Option List
• 3. Implementation: Clop Entry Points
• 3.1. A New Driver
• 3.2. Invoking the Parser
• 3.3. The Clop Class
• 3.4. Creating a Clop Instance
• 3.5. Parsing Option Definitions: the Idea
• 3.6. Parsing Option Definitions: the Method
• 3.7. Parsing Command Line Options: the Idea
• 3.8. Parsing Command Line Options: the Method
• 3.9. Printing Values
• 4. The First Journey: Clop, the Non-help Part
• 4.1. Three Journeys
• 4.2. Inspecting find_option
• 4.3. The Last Cryptic Bit
• 4.4. Inspecting parse_option
• 4.5. Extracting the Value: Normal Case
• 4.6. Extracting the Value: Compact Case
• 4.7. Interesting or Confusing?
• 4.8. Extracting the Value: Vector Case
• 4.9. Inspecting initialize_global_variables
• 5. The Second Journey: Clop_option
• 5.1. Code Listing
• 5.2. Parsing An Option Definition
• 5.3. Are we Done Yet?
• 5.4. A Non-Greedy Wild Card
• 5.5. Extracting the Name from a Definition
• 5.6. Extracting the Content from a Definition
• 5.7. Two Types of Mistakes
• 6. More Parsing of Single Lines
• 6.1. Recognizing the Type
• 6.2. Default Values
• 6.3. A Matter of Principles
• 6.4. Descriptions
• 6.5. Reflections on Ruby
• 6.6. A Comic Book Code Line
• 6.7. Evaluating Values
• 7. Initial State Output
• 7.1. The to_s Method
• 7.2. The Header Option
• 7.3. A Boolean Option
• 7.4. A Hack
• 7.5. A Vector Option
• 7.6. A Pyramid of Evaluations
• 8. The Third Journey: Clop, the Help Part
• 8.1. Two forms of Help
• 8.2. Help for Selected Options
• 8.3. Parsing Help
• 8.4. Printing Help: the Idea
• 8.5. Printing Help: the Method
• 8.6. What is Needed When
• 8.7. The Finishing Touch
• 9. A Built-In Test Facility
• 9.1. Testing Without a Driver
• 9.2. Required Options
• 9.3. A Boolean Option
• 9.4. A Vector Option
• 9.5. A Star Type Option
• 9.6. No Comment
• 9.7. The Answer
• 10. The Clop Code
• 10.1. Test Drivers
• 10.2. Code Listing
• 11. Literature References