Ruby RegEx by Liah Hansen

1. /regex will find me/ Regular Expressions

2. What are Regular Expressions Regular expressions allow matching and manipulation of textual data. Abbreviated as regex or regexp, or alternatively, just patterns

3. Regular Expressions in Ruby

4. Using Regular Expressions Scan a string for multiple occurrences of a pattern. Replace part of a string with another string. Split a string based on a matching separator.

7. Regex Basics [abc] A single character: a, b or c [^abc] Any single character but a, b, or c [a-z] Any single character in the range a-z [a-zA-Z] Any single character in the range a-z or A-Z ^ Start of line $ End of line Start of string End of string

8. Regex Basics cont... . Any single character Any whitespace character Any non-whitespace character Any digit Any non-digit Any word character (letter, number, underscore) Any non-word character Any word boundary character

9. Regex Basics cont... (...) Capture everything enclosed (a|b) a or b a? Zero or one of a a* Zero or more of a a+ One or more of a a{3} Exactly 3 of a a{3,} 3 or more of a a{3,6} Between 3 and 6 of a

10. Regex: .match >> category = "power tools" => "power tools" >> puts "on Sale" if category.match(/power tools/) on Sale >> puts "on Sale" if /power tools/.match(category) on Sale

11. Regex: =~ >> category = "shoes" => "shoes" >> puts "15 % off" if category =~ /shoes/ 15 % off >> puts "15 % off" if /shoes/ =~ category 15 % off >> /pants/ =~ category => nil >> /shoes/ =~ category => 0 >> category = "women's shoes” >> /shoes/ =~ category => 8 8th character

12. Scan >> numbers = "one two three" => "one two three" >> numbers.scan(/+/) => ["one", "two", "three”]

13. Split with Regular Expressions >> "one twothree".split(//) => ["one", ”two", "three"]

14. gsub ”fred,mary,john".gsub(/fred/, “XXX”) => “XXX,mary,john”

15. gsub with a block "one twothree".gsub(/(+)/) do |w| puts w end one two three

16. Title Case Capitalize All Words of a Sentence: >> full_name.gsub(//){|s| s.upcase} => "Yukihiro Matsumoto"