What I Learned From 55* Swift Standard Library Protocols

What I Learned From 55* Swift Standard Library Protocols by
@gregheo

@gregheo 55* Protocols 18 Minutes

@gregheo Why Protocols?

@gregheo Multiple Inheritance

@gregheo Animal Feline Canine Doge Pug Liger Jagwyre

@gregheo Animal Two Legs Canine Doge Pug Noisy Four Legs
Not Noisy etc. etc.

@gregheo

@gregheo 1. Protocol all the things 2. Open source it
3. ??? 4. Proﬁt! ⭐

@gregheo AbsoluteValuable, AnyCollectionType, AnyObject, ArrayLiteralConvertible, BidirectionalIndexType, BitwiseOperationsType, BooleanLiteralConvertible, BooleanType, CVarArgType,
CollectionType, Comparable, CustomDebugStringConvertible, CustomLeafReﬂectable, CustomPlaygroundQuickLookable, CustomReﬂectable, CustomStringConvertible, DictionaryLiteralConvertible, Equatable, ErrorType, ExtendedGraphemeClusterLiteralConvertible, FloatLiteralConvertible, FloatingPointType, ForwardIndexType, GeneratorType, Hashable, Indexable, IntegerArithmeticType, IntegerLiteralConvertible, IntegerType, IntervalType, LazyCollectionType, LazySequenceType, MirrorPathType, MutableCollectionType, MutableIndexable, MutableSliceable, NilLiteralConvertible, OptionSetType, OutputStreamType, RandomAccessIndexType, RangeReplaceableCollectionType, RawRepresentable, ReverseIndexType, SequenceType, SetAlgebraType, SignedIntegerType, SignedNumberType, Streamable, Strideable, StringInterpolationConvertible, StringLiteralConvertible, UnicodeCodecType, UnicodeScalarLiteralConvertible, UnsignedIntegerType

CollectionType, Comparable, CustomDebugStringConvertible, CustomLeafReﬂectable, CustomPlaygroundQuickLookable, CustomReﬂectable, CustomStringConvertible, DictionaryLiteralConvertible, Equatable, ErrorType, ExtendedGraphemeClusterLiteralConvertible, FloatLiteralConvertible, FloatingPointType, ForwardIndexType, GeneratorType, Hashable, Indexable, IntegerArithmeticType, IntegerLiteralConvertible, IntegerType, IntervalType, LazyCollectionType, LazySequenceType, MirrorPathType, MutableCollectionType, MutableIndexable, MutableSliceable, NilLiteralConvertible, OptionSetType, OutputStreamType, RandomAccessIndexType, RangeReplaceableCollectionType, RawRepresentable, ReverseIndexType, SequenceType, SetAlgebraType, SignedIntegerType, SignedNumberType, Streamable, Strideable, StringInterpolationConvertible, StringLiteralConvertible, UnicodeCodecType, UnicodeScalarLiteralConvertible, UnsignedIntegerType 1. Can do 2. Is a 3. Can be

@gregheo

@gregheo -able

@gregheo Hashable your instance → Int

@gregheo Equatable Comparable == != > < >= <=

@gregheo AbsoluteValuable public static func abs(x: Self) -> Self

@gregheo RawRepresentable instance ↔ raw value

@gregheo CustomPlaygroundQuickLookable instance → quick look view

@gregheo Operations Alternate Views So what?

@gregheo Image Filterable filtered image Video filtered video Audio filtered
audio

@gregheo protocol Thumbnailable { func thumbnailRepresentation() -> Self }

@gregheo Filterable Thumbnailable ↳ Can have a ﬁlter applied to
it ↳ Has an alternate thumbnail view

@gregheo Thing many many operations

@gregheo

@gregheo -Type

@gregheo CollectionType • Array • Dictionary • Set • Range
• String views

@gregheo IntegerType FloatingPointType BooleanType

@gregheo public protocol MirrorPathType // Do not declare new conformances
to this // protocol; they will not work as expected. 

@gregheo ErrorType (To throw when handling errors)

@gregheo SequenceType GeneratorType (For iteration support)

@gregheo Protocols as Identity So what?

@gregheo Animal Four Legs Barks Mammal Canine

@gregheo Legs Two Legs Doge Liger Barks Four Legs Meows
Meme Friendly

@gregheo

@gregheo -Convertible

@gregheo FloatLiteralConvertible IntegerLiteralConvertible ArrayLiteralConvertible

@gregheo FloatLiteralConvertible init(floatLiteral value: FloatLiteralType) Float Your Type

@gregheo CustomStringConvertible String Your Type

@gregheo ExtendedGraphemeClusterLiteralConvertible

@gregheo Protocols for Convertibility So what?

@gregheo Contractor Employee Manager

@gregheo protocol EmployeeConvertible { func hire() -> Employee } class
Contractor: EmployeeConvertible { // ... } class Interviewee: EmployeeConvertible { // ... }

@gregheo Contractor Interviewee can be an Employee can be an
Employee

@gregheo Contractor Interviewee EmployeeConvertible can be an Employee

@gregheo protocol EmployeeConvertible { func hire() -> Employee } class
Contractor: EmployeeConvertible { // ... } class Interviewee: EmployeeConvertible { // ... }

@gregheo 1. Operations 2. Alternate views 3. Identity 4. Conversion

@gregheo

Protocols FTW! @gregheo use them! say hello! wow

What I Learned From 55* Swift Standard Library ...

What I Learned From 55* Swift Standard Library Protocols

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