Putting the Fun in Functional - AndroidListener Chicago, October 2015

My talk on being a crazy person who decided to rebuild map, filter, and reduce functions in Java 7 so I could better understand what the hell they're doing.

And also on sandwiches.

Code be here: https://github.com/designatednerd/FunInFunctional-Android

Transcript

1. Putting the
   Fun*
   in Functional
   * - may depend on your definition of fun
   by Ellen Shapiro
   AndroidListener Chicago, October 2015
   

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2. The Big 3 Functional Methods
   map
   filter
   reduce
   

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4. What do these methods DO?
   -map: Apply the same function to everything in this
   collection
   

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5. What do these methods DO?
   -map: Apply the same function to everything in this
   collection
   -filter: Return the things in this collection passing a
   test function
   

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6. What do these methods DO?
   -map: Apply the same function to everything in this
   collection
   -filter: Return the things in this collection passing a
   test function
   -reduce: Combine the things in this collection with a
   starting value, and a function that adds things to a
   starting value.
   

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10. Demo Time!
    

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11. Don't Do What
    Donny Don't Did
    (At least if you
    want to be
    functional)
    

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12. Side effects!
    

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15. Question Time!
    

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16. Links!
    — Sample Code: https://github.com/designatednerd/
    FunInFunctional-Android
    

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17. Photo Credits!
    — Sandwich photo by Molly Elliot: https://
    www.flickr.com/photos/mollyelliott/4576766142
    — Square peg in a round hole photo by Yoel Ben-
    Avraham: https://www.flickr.com/photos/epublicist/
    3546059144
    — Pills by Thirteen of Clubs: https://www.flickr.com/
    photos/thirteenofclubs/
    

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