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
RecordDotSyntaxのあれこれ
Search
lotz
December 11, 2019
Programming
2
1.1k
RecordDotSyntaxのあれこれ
lotz
December 11, 2019
Tweet
Share
More Decks by lotz
See All by lotz
Recursion Schemesで考える並べ替えアルゴリズム
lotz84
6
2k
関数と型で理解する自動微分
lotz84
6
3k
Other Decks in Programming
See All in Programming
TFLintカスタムプラグインで始める Terraformコード品質管理
bells17
2
350
CSC509 Lecture 07
javiergs
PRO
0
240
実践Claude Code:20の失敗から学ぶAIペアプログラミング
takedatakashi
16
6.5k
コード生成なしでモック処理を実現!ovechkin-dm/mockioで学ぶメタプログラミング
qualiarts
0
240
Domain-centric? Why Hexagonal, Onion, and Clean Architecture Are Answers to the Wrong Question
olivergierke
3
940
Google Opalで使える37のライブラリ
mickey_kubo
3
130
pnpm に provenance のダウングレード を検出する PR を出してみた
ryo_manba
1
150
あなたとKaigi on Rails / Kaigi on Rails + You
shimoju
0
180
品質ワークショップをやってみた
nealle
0
600
なんでRustの環境構築してないのにRust製のツールが動くの? / Why Do Rust-Based Tools Run Without a Rust Environment?
ssssota
2
1.6k
SODA - FACT BOOK(JP)
sodainc
1
8.6k
NixOS + Kubernetesで構築する自宅サーバーのすべて
ichi_h3
0
1.1k
Featured
See All Featured
Done Done
chrislema
185
16k
Context Engineering - Making Every Token Count
addyosmani
7
290
Practical Orchestrator
shlominoach
190
11k
The Cult of Friendly URLs
andyhume
79
6.6k
For a Future-Friendly Web
brad_frost
180
10k
Building a Modern Day E-commerce SEO Strategy
aleyda
44
7.8k
Scaling GitHub
holman
463
140k
Git: the NoSQL Database
bkeepers
PRO
431
66k
Why You Should Never Use an ORM
jnunemaker
PRO
59
9.6k
How GitHub (no longer) Works
holman
315
140k
How to Create Impact in a Changing Tech Landscape [PerfNow 2023]
tammyeverts
55
3k
A designer walks into a library…
pauljervisheath
209
24k
Transcript
Record Dot Syntax ͷ͋Ε͜Ε By lotz 2019/12/11 ୈ2ճGHCษڧձ @ IIJ-II
RecordDotSyntax https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#motivation
RecordDotSyntaxͷجຊ https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#recorddotsyntax-language-extension
RecordDotSyntaxͷੜߏจ https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#recorddotsyntax-language-extension
Recordվળͷ্ʹ͋Δ ()$֦ு1SPQPTBM ()$7FSTJPO %VQMJDBUF3FDPSE'JFMET 0WFSMPBEFE-BCFMT 0WFSMPBEFE3FDPSE'JFMET "EETFU'JFMEUP)BT'JFME
/P'JFME4FMFDUPST "DDFQUFE 3FDPSE%PU4ZOUBY /&8
DAMLͰͷ࣮͋Γ • DAMLHaskell/ScalaͰ։ൃ͞Ε͍ͯΔɺ εϚʔτίϯτϥΫτهड़ݴޠ • DAMLͷ։ൃʹ͓͍ͯGHC Pluginsͱ͍͏ܗͰ RecordDotSyntaxͱ΄΅ಉ͡ػೳ͕ΘΕ͍ͯΔ
ఏҊͯ͠ΔͷDAMLͷਓ https://github.com/ghc-proposals/ghc-proposals/pull/282
PRͷԠ https://github.com/ghc-proposals/ghc-proposals/pull/282#issuecomment-540968106 *TUSPOHMZTVQQPSUUIFEJSFDUJPOPG USBWFMPGUIJTQSPQPTBM
PRͷԠ 5IFMPTTPGQPMZNPSQIJDVQEBUFJT BIVHFQSPCMFN JNP https://github.com/ghc-proposals/ghc-proposals/pull/282#issuecomment-541111003
PRͷԠ 5IJTQSPQPTBMJTGVMMPGVUUFSOPOTFOTF https://github.com/ghc-proposals/ghc-proposals/pull/282#issuecomment-541460439
> :t (.age) (.age) :: Person -> Int > :t
(. age) (. age) :: (Int -> c) -> Person -> c ۭനͷ༗Γແ͠Ͱ͜͜·Ͱҙຯ͕มΘΔͷ ॳ৺ऀʹ͘͠ͳ͍ʁ
ࠓͷεςʔλε https://github.com/ghc-proposals/ghc-proposals/pull/282#issuecomment-559259994 8JUIUIFUIDPNNFOU BGUFSSFBDUJPOTPOUIFJOJUJBM QPTU QBSUJDJQBOUTBOEBUMFBTUQPMMTPGVTFSTFOUJNFOU *EMJLFUPUVSOUIJTPWFSUPUIFDPNNJUUFF
ະղܾ https://twitter.com/ndm_haskell/status/1190680324495302658
͋Ε͜Ε
f a.b.c x ͷύʔε f a.foo.bar.baz.quux 12 f (a.foo.bar.baz.quux)
12 ͱධՁ͞ΕΔ ((f a).foo.bar.baz.quux) 12Ͱͳ͍ https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#record-selection
Lensʁ • f $ record ^. field ͕ f record.field
ͱॻ͚Δ • Lensෳࡶա͗Δ… • Lensͱ໊લۭ͕ؒҟͳΔͷͰҰॹʹ͑Δ https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#alternatives-to-this-proposal
͜͏͍͏දهແ͍ • ߋ৽ʹؔ͢Δߏจ • a{field * 2} • a{field <-
(*2)} • a{field * = 2} • ߋ৽ʹؔ͢ΔηΫγϣϯ • ({a=}) • ({a=b}) • (.lbl=) https://github.com/shayne-fletcher-da/ghc-proposals/blob/record-dot-syntax/proposals/0000-record-dot-syntax.md#alternatives-within-this-proposal
Ҏ্