Optionals, Protocols and Extensions - Swift by Example - SoCal Code Camp '16

Whether you are working with Swift as your first language or if you are coming from another language, Swift has some quirks setting it apart from other languages.

We will explore some of the reasonings, implementations and usages of these elements in the language through practical examples. Some of the Swift concepts we will be looking at are Optionals, Protocols and Extensions.

Transcript

1. Optionals, Protocols
   and Extensions
   Swift by Example
   @kickinbahk
   Josiah Mory
   

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2. Swift
   from a High Level
   

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3. Aims to be Objective-C
   without the C
   

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4. Swift is Type Safe
   

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5. Optionals
   

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6. Provide compile-time check that would
   prevent some common programming
   errors happened at run-time.
   

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7. Optionals require a
   discussion about NIL
   

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8. Reinforce the nil-check and
   offer compile-time cues
   

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9. Assumes a value must be
   present, unless told otherwise
   

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10. An optional must be
    unwrapped using a ? or !
    

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11. Protocols
    

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12. Blueprint
    

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13. A blueprint of methods, properties,
    and other requirements that suit a
    particular task or piece of functionality
    

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15. Contract
    

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16. A guarantee of some terms that will
    be satisfied. To the other party, the
    contract is a set of obligations.
    

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18. Abstraction Layer
    

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19. Allows us to Create
    Delegates
    

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20. Class that adopts the protocol
    is referred to as the ‘Delegate’
    

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21. One class (a delegator class) would give
    control or responsibility for some behavioral
    logic to another class called a delegate.
    

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22. 1. Create a delegate protocol that
    defines the responsibilities of the
    delegate.
    

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23. 2. Create a delegate property in
    the delegating class to keep track
    of the delegate.
    

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24. 3. Adopt and implement the
    delegate methods in the delegate
    class.
    

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25. 4. Call the delegate from the
    delegating object.
    

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26. Extensions
    

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27. Added functionality to a
    Class, Struct or Enum
    

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28. Adding functionality…
    Not overwriting it
    

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29. NO Monkey Patching From Extensions
    

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30. Increases Readability
    

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31. Thank you!
    

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