Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
self in return type declaration
Search
DQNEO
June 27, 2018
Technology
1
180
self in return type declaration
PHPの戻り値型宣言でselfを使ってみよう
DQNEO
June 27, 2018
Tweet
Share
More Decks by DQNEO
See All by DQNEO
英和辞書付きGo言語仕様書 / Word Wise Go Spec
dqneo
1
530
Go言語低レイヤー入門 Hello world が 画面に表示されるまで / Introduction to low level programming in Go
dqneo
6
1.6k
入門Go言語仕様 / Go Specification Untyped Constants
dqneo
1
1.3k
入門Go言語仕様 Underlying Type / Go Language Underlying Type
dqneo
9
5k
How to write a self hosted Go compiler from scratch (Gophercon 2020)
dqneo
3
1.6k
もっと気軽にOSSに Pull Requestを出そう!/ Let's make a PR to OSS more easily
dqneo
6
8.3k
Goコンパイラをゼロから作ってセルフホスト達成するまで / How I wrote a self hosted Go compiler from scratch
dqneo
15
14k
コンパイラをつくってみよう / How to make a compiler
dqneo
9
11k
コンパイラ作りの魅力を語る / Making compilers is fun
dqneo
10
8.5k
Other Decks in Technology
See All in Technology
Reach American Airlines®️ Instantly: 19 Calling Methods for Fast Support in the USA
flyamerican
1
160
PO初心者が考えた ”POらしさ”
nb_rady
0
210
SmartNewsにおける 1000+ノード規模 K8s基盤 でのコスト最適化 – Spot・Gravitonの大規模導入への挑戦
vsanna2
0
130
B2C&B2B&社内向けサービスを抱える開発組織におけるサービス価値を最大化するイニシアチブ管理
belongadmin
1
6.9k
関数型プログラミングで 「脳がバグる」を乗り越える
manabeai
1
190
DBのスキルで生き残る技術 - AI時代におけるテーブル設計の勘所
soudai
PRO
47
19k
LangSmith×Webhook連携で実現するプロンプトドリブンCI/CD
sergicalsix
1
230
整頓のジレンマとの戦い〜Tidy First?で振り返る事業とキャリアの歩み〜/Fighting the tidiness dilemma〜Business and Career Milestones Reflected on in Tidy First?〜
bitkey
2
16k
「クラウドコスト絶対削減」を支える技術—FinOpsを超えた徹底的なクラウドコスト削減の実践論
delta_tech
4
170
Tokyo_reInforce_2025_recap_iam_access_analyzer
hiashisan
0
180
無意味な開発生産性の議論から抜け出すための予兆検知とお金とAI
i35_267
4
13k
united airlines ™®️ USA Contact Numbers: Complete 2025 Support Guide
flyunitedhelp
1
300
Featured
See All Featured
Dealing with People You Can't Stand - Big Design 2015
cassininazir
367
26k
The Pragmatic Product Professional
lauravandoore
35
6.7k
個人開発の失敗を避けるイケてる考え方 / tips for indie hackers
panda_program
107
19k
How GitHub (no longer) Works
holman
314
140k
Java REST API Framework Comparison - PWX 2021
mraible
31
8.7k
Building Applications with DynamoDB
mza
95
6.5k
Typedesign – Prime Four
hannesfritz
42
2.7k
Refactoring Trust on Your Teams (GOTO; Chicago 2020)
rmw
34
3.1k
How to train your dragon (web standard)
notwaldorf
95
6.1k
"I'm Feeling Lucky" - Building Great Search Experiences for Today's Users (#IAC19)
danielanewman
229
22k
BBQ
matthewcrist
89
9.7k
Cheating the UX When There Is Nothing More to Optimize - PixelPioneers
stephaniewalter
281
13k
Transcript
!%2/&0 Ͳ͖ΎͶ͓ BU.FSDBSJ QIQTUVEZ lTFMGzJO 3FUVSO5ZQF%FDMBSBUJPO
(JUຊͷम͠·ͨ͠
3FUVSOUZQFEFDMBSBUJPO Γͷܕએݴ ͬͯ·͔͢ʁ
function foo(): int { } Γͷܕએݴͱʁ ͜Μͳͭ
ྫɿࣗΛฦ͢ϝιου class A { public function getMe(): A { return
$this; } }
࣮TFMGͱॻ͚Δ class A { public function getMe(): self { return
$this; } }
ΜΓʂʂ
ҙ֎ͱΒͳ͍ਓ ଟ͍ҹ
ެࣜυΩϡϝϯτʹ ͳ͔ͥTFMGʹ͍ͭͯ ݴٴͳ͠ IUUQQIQOFUNBOVBMFOGVODUJPOTSFUVSOJOH WBMVFTQIQGVODUJPOTSFUVSOJOHWBMVFTUZQFEFDMBSBUJPO
3'$ͷԼͷํʹখ͞ʙ͘ ॻ͍ͯ͋Δ IUUQTXJLJQIQOFUSGDSFUVSO@UZQFT
ܧঝ͢ΔͱͲ͏ͳΔʁ class A { public function getMe(): self { return
$this; } } class B extends A {} $b = new B(); $b->getMe(); // ?
ਖ਼ղ#ͷΠϯελϯε͕ฦΔ class A { public function getMe(): self { return
$this; } } class B extends A {} $b = new B(); $b->getMe(); // instance of B
UIJTɺ#ͷίϯςΩε τ͔ΒݺΕΔͱ#ͷΠ ϯελϯεΛࢦ͢ͷͰɻ
ࠨͷίʔυӈͷίʔυͱՁ class A { public function getMe(): A { return
$this; } } class B extends A {} $b = new B(); $b->getMe(); // B class A { public function getMe(): self { return $this; } } class B extends A {} $b = new B(); $b->getMe(); // B
Γͷܕɺ ࣮ߦ࣌ʹSFUVSO͞Εͨࡍʹ JOTUBODFPG తͳͷͰ ͰνΣοΫ͞ΕΔ
͜ͷ߹Ͳ͏ͳΔʁ class A { public function getMe(): self { return
$this; } } class B extends A { public function getMe(): self { return $this; } }
'BUBMFSSPS ࣮ߦ࣌ίϯύΠϧΤϥʔ 1)1'BUBMFSSPS %FDMBSBUJPOPG#HFU.F #NVTUCFDPNQBUJCMFXJUI "HFU.F "
͜Ε͕μϝͳͷͱಉ͡ γάωνϟͷෆҰக class A { public function getMe(): A
… } class B extends A { public function getMe(): B … }
͜͏͢Ε͓̺ class A { public function getMe(): self { return
$this; } } class B extends A { public function getMe(): parent { return $this; } }
͜Ε͕0,ͳͷͱಉ͡ class A { public function getMe(): A … }
class B extends A { public function getMe(): A … }
༨ஊɿ͜Εকདྷͷ1)1Ͱ ՄೳʹͳΔ͔͠Εͳ͍ɻ Γͷڞม class A { public function getMe():
A } class B extends A { public function getMe(): B … } IUUQTXJLJQIQOFUSGDDPWBSJBOUSFUVSOTBOE DPOUSBWBSJBOUQBSBNFUFST
ͪͳΈʹܕ໊ͷͱ͜Ζʹ TUBUJDෆՄɻ class A { public function getMe(): static …
}
·ͱΊ w ΓܕએݴͰTFMG QBSFOU ͕͑Δ w ཚ༻͢ΔͱΘ͔Γʹ͘͘ͳΔ ͷͰదࡐదॴͰ w ʮJOTUBODFPGνΣοΫʯͩͱ
ࢥ͓̺͑
༨ஊɿϝιουͷҾͰ͑Δ class A { public function setMe(self $self) { $this->self
= $self; } } class B extends A { public function setMe(parent $self) { $this->self = $self; } }
͝ਗ਼ௌ͋Γ͕ͱ͏ ͍͟͝·ͨ͠ NN