You are previewing Learning Ruby.

Learning Ruby

Cover of Learning Ruby by Michael Fitzgerald Published by O'Reilly Media, Inc.
  1. Learning Ruby
    1. SPECIAL OFFER: Upgrade this ebook with O’Reilly
    2. A Note Regarding Supplemental Files
    3. Preface
      1. Who Should Read This Book?
      2. How This Book Works
      3. About the Examples
      4. How This Book Is Organized
      5. Conventions Used in This Book
      6. Comments and Questions
      7. Safari® Enabled
      8. Acknowledgments
    4. 1. Ruby Basics
      1. Hello, Matz
      2. Interactive Ruby
      3. Resources
      4. Installing Ruby
      5. Permission Denied
      6. Associating File Types on Windows
      7. Review Questions
    5. 2. A Quick Tour of Ruby
      1. Ruby Is Object-Oriented
      2. Ruby's Reserved Words
      3. Comments
      4. Variables
      5. Strings
      6. Numbers and Operators
      7. Conditional Statements
      8. Arrays and Hashes
      9. Methods
      10. Blocks
      11. Symbols
      12. Exception Handling
      13. Ruby Documentation
      14. Review Questions
    6. 3. Conditional Love
      1. The if Statement
      2. The case Statement
      3. The while Loop
      4. The loop Method
      5. The for loop
      6. Execution Before or After a Program
      7. Review Questions
    7. 4. Strings
      1. Creating Strings
      2. Concatenating Strings
      3. Accessing Strings
      4. Comparing Strings
      5. Manipulating Strings
      6. Case Conversion
      7. Managing Whitespace, etc.
      8. Incrementing Strings
      9. Converting Strings
      10. Regular Expressions
      11. 1.9 and Beyond
      12. Review Questions
    8. 5. Math
      1. Class Hierarchy and Included Modules
      2. Converting Numbers
      3. Basic Math Operations
      4. Ranges
      5. Inquiring About Numbers
      6. More Math Methods
      7. Math Functions
      8. Rational Numbers
      9. Prime Numbers
      10. Review Questions
    9. 6. Arrays
      1. Creating Arrays
      2. Accessing Elements
      3. Concatenation
      4. Set Operations
      5. Unique Elements
      6. Blow Your Stack
      7. Comparing Arrays
      8. Changing Elements
      9. Deleting Elements
      10. Arrays and Blocks
      11. Sorting Things and About Face
      12. Multidimensional Arrays
      13. 1.9 and Beyond
      14. Other Array Methods
      15. Review Questions
    10. 7. Hashes
      1. Creating Hashes
      2. Accessing Hashes
      3. Iterating over Hashes
      4. Changing Hashes
      5. Converting Hashes to Other Classes
      6. 1.9 and Beyond
      7. Other Hash Methods
      8. Review Questions
    11. 8. Working with Files
      1. Directories
      2. Creating a New File
      3. Opening an Existing File
      4. Deleting and Renaming Files
      5. File Inquiries
      6. Changing File Modes and Owner
      7. The IO Class
      8. Review Questions
    12. 9. Classes
      1. Defining the Class
      2. Instance Variables
      3. Accessors
      4. Class Variables
      5. Class Methods
      6. Inheritance
      7. Modules
      8. public, private, or protected
      9. Review Questions
    13. 10. More Fun with Ruby
      1. Formatting Output with sprintf
      2. Processing XML
      3. Date and Time
      4. Reflection
      5. Using Tk
      6. Metaprogramming
      7. RubyGems
      8. Exception Handling
      9. Creating Documentation with RDoc
      10. Embedded Ruby
      11. Review Questions
    14. 11. A Short Guide to Ruby on Rails
      1. Where Did Rails Come From
      2. Why Rails?
      3. What Have Other Folks Done with Rails?
      4. Hosting Rails
      5. Installing Rails
      6. Learning Rails
      7. A Brief Tutorial
      8. Review Questions
    15. A. Ruby Reference
      1. Ruby Interpreter
      2. Ruby's Reserved Words
      3. Operators
      4. Escape Characters
      5. Predefined Variables
      6. Global Constants
      7. Regular Expressions
      8. String Unpack Directives
      9. Array Pack Directives
      10. Sprintf Flags and Field Types
      11. File Tests
      12. Time Formatting Directives
      13. RDoc Options
      14. Rake
    16. B. Answers to Review Questions
      1. Chapter 1 Review Questions
      2. Chapter 2 Review Questions
      3. Chapter 3 Review Questions
      4. Chapter 4 Review Questions
      5. Chapter 5 Review Questions
      6. Chapter 6 Review Questions
      7. Chapter 7 Review Questions
      8. Chapter 8 Review Questions
      9. Chapter 9 Review Questions
      10. Chapter 10 Review Questions
      11. Chapter 11 Review Questions
    17. Glossary
    18. Index
    19. About the Author
    20. Colophon
    21. SPECIAL OFFER: Upgrade this ebook with O’Reilly
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String Unpack Directives

Table A-7 lists unpack directives for String#unpack.

Table A-7. String unpack directives

Directive

Returns

Description

A

String

Removes trailing nulls and spaces

a

String

String

B

String

Extracts bits from each character (most significant bit first)

b

String

Extracts bits from each character (least significant bit first)

C

Fixnum

Extracts a character as an unsigned integer

c

Fixnum

Extracts a character as an integer

d, D

Float

Treats sizeof(double) characters as a native double

E

Float

Treats sizeof(double) characters as a double in little-endian byte order

e

Float

Treats sizeof(float) characters as a float in little-endian byte order

f, F

Float

Treats sizeof(float) characters as a native float

G

Float

Treats sizeof(double) characters as a double in network byte order

g

Float

Treats sizeof(float) characters as a float in network byte order

H

String

Extracts hex nibbles from each character (most significant bit first)

h

String

Extracts hex nibbles from each character (least significant bit first)

I

Integer

Treats sizeof(int) (modified by _) successive characters as an unsigned native integer

i

Integer

Treats sizeof(int) (modified by _) successive characters as a signed native integer

L

Integer

Treats four (modified by _) successive characters as an unsigned native long integer

l

Integer

Treats four (modified by _) successive characters as a signed native long integer

M

String

Quoted-printable

m

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