Ruby Method of the Month 2010.04. Lightning talk for the Columbus Ruby Brigade.

1. MOTM: Take & Drop
Kevin Munc — @muncman

2. Taking

3. take & take_while
take(n) gives you the first n elements
take_while { |elem| block } gives you
elements until the block condition is nil or
false
Works on Array and Enumerable

4. take
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.take(5)
=> [0,1,2,3,4]

5. take
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.take(5)
=> [0,1,2,3,4]
uhray = []
uhray.take(5)
=> []

6. take_while
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.take_while { |item| item < 6 }
=> [0,1,2,3,4,5]

7. take_while
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.take_while { |item| item < 6 }
=> [0,1,2,3,4,5]
uhray.take_while { |item| item > 6 }
=> []

8. Dropping

9. drop & drop_while
drop(n) gives you all elements after the first
n elements
drop_while { |elem| block } gives you all
elements starting when the block condition
is nil or false
Works on Array and Enumerable

10. drop
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.drop(5)
=> [5,6,7,8,9]

11. drop
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.drop(5)
=> [5,6,7,8,9]
uhray = []
uhray.drop(5)
=> []

12. drop_while
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.drop_while { |item| item < 6 }
=> [6,7,8,9]

13. drop_while
uhray = [0,1,2,3,4,5,6,7,8,9]
uhray.drop_while { |item| item < 6 }
=> [6,7,8,9]
uhray.drop_while { |item| item > 6 }
=> [0,1,2,3,4,5,6,7,8,9]

14. Questions?
Built on an iPad
Photo Credits
http://www.flickr.com/photos/stevewall/802936876/
http://www.flickr.com/photos/z6p6tist6/3967592710/
http://www.flickr.com/photos/whosdadog/3652663745/