UWE-Ruby Week 4 Class Slides

1. Ruby
Week 4

2. HomeWork Review
• Calculator
• Collections
• Inject

3. Numbers
• FixNum
• 1 is always 1! (unlike strings)
• Floats (BigDecimal)
• 4.2
• 3.141516

4. Ranges
• 1..5
• 1...5
• a..z
• OddNumber.new(1)..OddNumber.new(5)

5. Symbols
• :symbols_are_fun
• A static name
• Stored like numbers, named like
strings!

6. Blocks
• A method with no name!
• Dynamic method definition

7. Block Syntax
• {}
• do
• <code>
• end

8. Blocks:
Calling and Checking
• yield
• call
• block_given?

9. Blocks with Parameters
• yield(x)
• call(x)
• {|x|}
• do |x|
• <code>
• end

10. Blocks Demo
• Time My Code!
• timer_spec.rb

11. Blocks Exercise
• Do My Work!
• worker_spec.rb

12. RegExp
• Surprise Guest Lecturer!

13. HomeWork
• Will be posted after class to the
homework folder.
• questions.txt
• something_spec.rb