Ruby by Example

Chapter Recap

What was new in this chapter?

• End-of-line differences among operating systems

• Regular expressions, including the ? counter

• The sprintf method

• Multiplication of Arrays

• The inject method

• Regular expressions with the + counter

• Objects as the results of blocks

• Calling successive methods on the output of methods (“chaining” methods)

• Using new methods of Open Classes in quick scripts

• Multiplication of Strings

• The grep method

• The map method

• The Range class

• Recursion

That’s quite a bit, including some important new functional concepts like recursion and a few very handy functional methods. You’ll need these concepts as we move on. Let’s proceed to some more complex treatment of numbers in Chapter 5.