Ruby by Example: Concepts and Code Book

Acknowledgments     xvii
Introduction: What is Ruby?     xix
Acquiring and Configuring Ruby     xx
On a Unix or Unix-like System     xx
On a Windows System     xxi
Motivations for the Book     xxi
Conventions     xxii
Summary of Chapters     xxii
Interactive Ruby and the Ruby Environment     1
Starting irb     2
Using irb     2
Expressions     2
Everything Is an Object     2
Integers, Fixnums, and Bignums     3
Addition, Concatenation, and Exceptions     4
Casting     4
Arrays     5
Booleans     6
Flow Control     6
Methods     8
Variables     9
Constants     10
Using the Ruby Interpreter and Environment     10
Amusements and Simple Utilities     13
Is It Payday? (check_payday.rb)     14
The Code     14
How It Works     14
The Results     16
Random Signature Generator (random_sig.rb and random_sig-windows.rb)     16
The Code     16
How It Works     16
Running the Script     19
The Results     19
Hacking the Script     19
The 99 Bottles of Beer Song (99bottles.rb)     20
The Code     20
How It Works     21
Running the Script     25
The Results     25
Sound File Player (shuffle_play.rb)     25
The Code     26
How It Works     27
Running the Script     29
The Results     29
Hacking the Script     30
Chapter Recap     31
Programmer Utilities     33
What Is Truth? (boolean_golf.rb)     33
The Code     34
How It Works     34
Hacking the Script     36
Running the Script     36
The Results     36
Making a List (array_join.rb)     36
The Code     37
How It Works     37
Running the Script     39
Hacking the Script     39
Command-Line Interface (uses_cli.rb and simple_cli.rb)     39
The Code     40
How It Works     42
Running the Script     44
Hacking the Script      45
Palindromes (palindrome.rb and palindrome2.rb)     45
The Code     45
How It Works     46
Hacking the Script     46
Running the Script     47
The Results     48
Chapter Recap     49
Text Manipulation     51
End-of-Line Conversion (dos2unix.rb)     51
The Code     52
How It Works     52
Running the Script     55
The Results     56
Hacking the Script     56
Showing Line Numbers (line_num.rb)     57
The Code     57
How It Works     57
Running the Script     58
The Results     58
Wrapping Lines of Text (softwrap.rb)     59
The Code     59
Running the Script     62
The Results     62
Hacking the Script     62
Counting Words in a File (word_count.rb)     62
The Code     63
How It Works     64
Running the Script     64
The Results     64
Word Histogram (most_common_words.rb)     65
The Code     65
How It Works      65
Running the Script     67
The Results     67
Hacking the Script     67
Rotating Characters in a String (rotate.rb)     68
The Code     68
How It Works     68
Running the Script     69
The Results     69
Chapter Recap     70
Number Utilities     71
Computing Powers (power_of.rb)     72
The Code     72
How It Works     73
Running the Script     74
The Results     75
Adding Commas to Numbers (commify.rb)     75
Inheritance     75
Modules     76
The Code     76
How It Works     78
Running the Script     81
The Results     81
Roman Numerals (roman_numeral.rb)     81
The Code     82
How It Works     83
Running the Script     86
The Results     86
Hacking the Script     87
Currency Conversion, Basic (currency_converter1.rb)     87
The Code     88
How It Works     89
Running the Script     90
The Results      90
Hacking the Script     90
Currency Conversion, Advanced (currency_converter2.rb)     90
The Code     91
How It Works     93
Running the Script     97
The Results     97
Hacking the Script     98
Chapter Recap     98
Functionalism with Blocks and Procs     99
Our First lambda (make_incrementer.rb)     100
The Code     100
How It Works     101
The Results     101
Using Procs for Filtering (matching_members.rb)     102
The Code     102
How It Works     102
Running the Script     103
The Results     103
Using Procs for Compounded Filtering (matching_compound_members.rb)     103
The Code     104
How It Works     105
The Results     107
Hacking the Script     108
Returning Procs as Values (return_proc.rb)     108
The Code     108
The Results     109
How It Works     109
Nesting lambdas     111
The Code     111
How It Works     112
Procs for Text (willow_and_anya.rb)     112
The Code     112
How It Works     115
Running the Script     118
The Results     118
Hacking the Script     119
Chapter Recap     119
Using, Optimizing, and Testing Functional Techniques     121
Basic Factorials and Fibonaccis (factorial1.rb through fibonacci5.rb)     122
The Code     122
How It Works     123
The Results     123
Hacking the Script     124
Benchmarking and Profiling (tests/test_opts.rb)     128
Benchmarking     128
The Code     128
How It Works     129
Running the Script     130
The Results     130
Profiling     131
Hacking the Script     132
Converting Temperatures (temperature_converter.rb)     132
The Code     132
How It Works     134
The Results     136
Hacking the Script     136
Testing temperature_converter.rb (tests/test_temp_converter.rb)     137
The Code     137
The Results     138
How It Works     139
Hacking the Script     139
Chapter Recap     140
HTML and XML Tools     141
Cleaning Up HTML (html_tidy.rb)     141
The Code     142
How It Works     144
Running the Script     146
The Results     147
Hacking the Script     148
Counting Tags (xml_tag_counter.rb)     148
The Code     149
How It Works     150
Running the Script     153
The Results     153
Hacking the Script     153
Extracting Text from XML (xml_text_extractor.rb)     154
The Code     154
How It Works     155
Running the Script     155
The Results     155
Hacking the Script     156
Validating XML (xml_well_formedness_checker.rb)     156
The Code     156
How It Works     157
Running the Script     158
The Results     158
Hacking the Script     158
Chapter Recap     159
More Complex Utilities and Tricks, Part I     161
Finding Codes in the Bible or Moby-Dick (els_parser.rb)     161
The Code      162
How It Works     164
Running the Script     167
The Results     167
Hacking the Script     168
Mutating Strings into Weasels (methinks.rb)     168
The Code     168
How It Works     171
Running the Script     174
The Results     174
Hacking the Script     175
Mutating the Mutation of Strings into Weasels (methinks_meta.rb)     176
The Code     177
How It Works     179
Running the Script     181
The Results     181
Hacking the Script     182
Chapter Recap     183
More Complex Utilities and Tricks, Part II     185
Overnight DJ (radio_playerl.rb)     186
The Code     186
How It Works     187
The Results     189
Hacking the Script     190
Better Overnight DJ (radio_player2.rb)     190
The Code     190
How It Works     191
The Results     192
Hacking the Script     193
Numbers by Name (to_lang.rb)     193
The Code     194
How It Works     198
The Results     201
Hacking the Script     202
Elegant Maps and Injects (symbol.rb)     203
The Code     203
How It Works     203
The Results     204
Hacking the Script     204
Chapter Recap     204
CGI and the Web     205
Common Gateway Interface     206
Preparation and Installation     206
A Simple CGI Script (simple_cgi.rb)     207
The Code     207
How It Works     208
The Results     210
Hacking the Script     210
Mod Ruby (mod_ruby_demo.rhtml and mod_ruby_demo.conf)     211
The Code     211
How It Works     213
The Results     214
Hacking the Script     214
CSS Stylesheets, Part I (stylesheet.rcss)     215
The Code     215
How It Works     216
The Results     217
Hacking the Script     218
CSS Stylesheets, Part II (stylesheet2.rcss)     218
The Code     218
How It Works     220
The Results     220
Hacking the Script     221
Chapter Recap      221
Rubygems and Rails Preparation     223
RubyGems     223
Installing RubyGems     224
Using RubyGems     224
Rails Preparation     227
What Is Rails?     228
Other Options for Installing Rails     228
Databases     229
The Structure of a Rails Application     229
Chapter Recap     235
A Simple Rails Project     237
Creating the Application     237
Initial Creation     238
Preparing the Database     238
Adding Data     238
Creating the Model and Controllers     240
Dissecting the Application     241
Dissecting the Photo Model     241
Dissecting the Controllers     242
Dissecting the Helpers     245
Dissecting the Album Controller's Views     251
Dissecting the Feed Controller's images View     254
Dissecting the Album Controller's Layout     256
Using CSS     257
Using the Application     257
Learning More About Rails     260
Chapter Recap     260
How does Ruby Compare to Other Languages?      261
C     261
Haskell     262
Java     262
Lisp     263
Perl     264
PHP     264
Python     265
Smalltalk     265
Summary of Ruby vs. Other Languages     266
Index     267