Swift 周報 4/12

Swift 周報 4/12

Transcript

1. Swift पใ 4/12 John Lin @johnlinvc
2. From the core • inliner ࠷ՂԽᩋࣥߦ䈕େখݮগ
3. inliner ࠷ՂԽᩋࣥߦ䈕େখݮগ • ࠷ՂԽ inliner ԋࢉ๏ᩋࣥߦ䈕େখݮগ • stdlib: 3% • Benchmarks_O: 9% • ၷݸେఔࣜ: 15%, 20%
4. Evolution • SE-0042 ἷฏԽ instance method references తܕผ • SE-0043 ࡏ༗ଟݸpatterns త case label தએࠂᏓ Ꮠ • SE-0044 Import C function ᗣ swift function • SE-0047 ༬ઃܯࠂᔒ༗࢖༻౸తճၚᆴ
5. ἷฏԽ instance method references తܕผ • ݱࡏ class Foo { func foo(bar:Int) { print(bar) } } Foo.foo(Foo())(3) // 3 • ະိ Foo.foo(Foo(),3) // 3
6. ࡏ༗ଟݸpatterns త case label தએࠂᏓᏐ • Լ໘Ҏޙ။ಈ let point = (2,2) switch point { case let (1,x), let (2,x): //error print(x) default: break }
7. Import C function ᗣ swift function • ݱࡏimport C function ޙ။Ꮣ੒global function • ະိՄҎࢦఆimport ਐိޙతҐஔɼ໵बੋՄҎࢦఆC function ੒ᗣ init, method, computed property, static property, static computed property ҃ੋ subscript • ࢖༻ __attribute__((swift_name(“SWIFT_NAME")));
8. Import C function ᗣ swift function // Import as init struct Point3D createPoint3D(float x, float y, float z) __attribute__((swift_name("Point3D.init(x:y:z:)"))); // Import as method struct Point3D rotatePoint3D(Point3D point, float radians) __attribute__((swift_name("Point3D.rotate(self:radians:)")));
9. ༬ઃܯࠂᔒ༗࢖༻౸తճၚᆴ • ᙛfunc ༗ճၚᆴɼୠੋᔒ༗ඃ༻౸త࣌ީሡ။༬ઃग़ݱܯࠂ func getScore()->Int { return 56 } var score = 0 getScore() //will raise warning print(score) • ݱࡏ༬ઃෆ။ܯࠂɼ༻@warn_unused_result ՄҎ㗞ੜܯ ࠂɻ • ະိ༬ઃܯࠂɼՄҎ༻@discardableResult ိऔফܯࠂɻ
10. Evolution • SE-0016 Unsafe[Mutable]Pointer ՄҎ᫚੒ Int • SE-0053 function ჩᏐதෆ࠶ՄҎ༗ let • SE-0054 Abolish ImplicitlyUnwrappedOptional type • SE-0055 ᩋUnsafe Pointer໵࢖༻Optional ိදࣔ nullability
11. Unsafe[Mutable]Pointer ՄҎ᫚੒ [U]Int • ՄҎ೺Pointer ᫚੒ Int ೭ޙ၏֤छӡࢉɻ • ᩋSwift ՄҎ၏ߋଟతܥ౷ఔࣜ
12. function ჩᏐதෆ࠶ՄҎ༗ let • function ჩᏐ໨લpass by value ޙ౎ੋෆೳվᏓతɼະ ိ။׬શෆೳࡏჩᏐલ໘ଧ let/var fun fLet(let a:Int) { print(a) } • ޷႔ɿະိ argument label ՄҎੋ೚Կ keyword func fc(let l:Int) { print(l) } fc(let: 10)
13. ᩋUnsafe Pointer໵࢖༻Optional ိ දࣔ nullability • ݱࡏᔒ༗㭎๏ኺType ؃ग़Pointer ༗ᔒ༗Մೳੋ NULL • ະိ Pointer ໵။Ճೖ Optional తޭೳ • if let ptr = nil_ptr {
 foo(ptr)
 }