The Future of Functional Programming on iOS

This is a presentation I gave at NSSpain 2014: http://nsspain.com/2014/

Code used in the presentation: https://github.com/AshFurrow/NSSpain2014

The "Functional Programming in Swift" book is available at http://www.objc.io/books/

The new Artsy Swift app written in ReactiveCocoa is available at http://github.com/artsy/eidolon

The Carl Sagan wallpaper was downloaded from http://picc.it/c/wallpapers/pictures/album/wallpaper_28/id/50302/@carl_sagan_wallpaper_i_made

Transcript

1. the$f&t&re$of
   Ash Furrow
   functional programming
   on$iOS
   

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2. Objective-C
   

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3. Objective-
   C
   

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4. Closures
   Functional patterns
   Concise syntax
   Native Collections
   Operator overloading
   Namespaces Tuples
   Clear mutability syntax
   Interactive playground Multiple return types
   Generics
   Protocols and extensions on structs
   Pattern matching
   Fast iteration
   Optional types
   Object orientation
   Type inference
   Read-Eval-Print-Loop (REPL)
   Compile to native code
   

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5. Closures
   Functional patterns
   Concise syntax
   Native Collections
   Operator overloading
   Namespaces Tuples
   Clear mutability syntax
   Interactive playground Multiple return types
   Generics
   Protocols and extensions on structs
   Pattern matching
   Fast iteration
   Optional types
   Object orientation
   Type inference
   Read-Eval-Print-Loop (REPL)
   Compile to native code
   

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6. Closures
   Functional patterns
   Concise syntax
   Native Collections
   Operator overloading
   Namespaces Tuples
   Clear mutability syntax
   Interactive playground Multiple return types
   Generics
   Protocols and extensions on structs
   Pattern matching
   Fast iteration
   Optional types
   Object orientation
   Type inference
   Read-Eval-Print-Loop (REPL)
   Compile to native code
   

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7. Objective-C
   

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8. Objective-
   C
   

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9. Objective-C
   

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11. It will not be we make apps for the WATCH 5
    and the other future iOS devices.
    It will be a group of developers very much like us.
    But with more of our strengths and fewer of our weaknesses.
    More confident, far-seeing,
    and capable of using functional paradigms.
    For all of our failings, despite our limitations and fallibilities,
    we developers are capable of greatness.
    —Carl Sagan
    

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12. 1. Imperative$prog5amming$is$old$and$busted$
    2.Functional$prog5amming$is$the$new$ho?@ess$
    3.Ge?ing$starCed$with$f&nctional$prog5amming$in$Swiſt$is$superEeasy
    

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13. old
    and
    busted
    

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14. BNE ADD1
    BRA NONE1
    ADD1 INY ;increment our counter of 1's
    NONE1 LDAA TEMP ;reload accumulator A
    LSL MASK ;Shift the mask's 1 bit left
    BNE LOOP1 ;If we haven't finished our loop, branch
    LDAA #$01 ;load new mask into A
    STAA MASK ;store the reset mask into MASK
    TSX ;pull of return address and store in X
    PULA ;pull off A
    STAA TEMP ;store the value into temp
    TXS ;push return address back onto the stack
    LOOP2 LDAA TEMP ;Load A into TEMP
    ANDA MASK ;logical AND MASK with A
    BNE ADD2 ;add one if we need to
    BRA NONE2
    ADD2 INY ;increment our counter of 1's
    NONE2 LDAA TEMP
    LSL MASK ;shift our mask left by one
    BNE LOOP2 ;loop back until we've exhausted positions
    

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15. new
    hottness
    

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16. functional programming
    • It’s been around forever
    • But only in universities (ew)
    

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17. what is functional programming?
    • Treat computation as the result of functions
    • Avoid mutable state and data
    

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18. f&nctional$prog5amming$tells$the$computer
    instead$of
    what to do
    how to do it
    

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19. getting started
    is
    super-fácil*
    *ed:$Spanish
    

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20. code
    let’s
    

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21. github.com/ashfurrow/nsspain2014
    [~]
    

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22. resources
    • Books
    • GitHub
    • ReactiveCocoa
    • swiftz
    • Stack Overflow
    • Tweet me
    

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23. objc.io/books
    

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24. github.com/artsy/eidolon
    

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25. 1. Imperative$prog5amming$is$old$and$busted$
    2.Functional$prog5amming$is$the$new$ho?@ess$
    3.Ge?ing$starCed$with$f&nctional$prog5amming$in$Swiſt$is$superEeasy
    

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26. so where now?
    • Swift promised functional patterns
    • Failed to deliver
    • Community is picking up the slack
    

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27. make
    better mistakes
    tomorrow
    

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28. gracias
    @ashfurrow
    

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