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
ジェネレータを有効活用し隊 / Kyoto.js 11 LT
Search
Susisu
October 22, 2016
Programming
2
2k
ジェネレータを有効活用し隊 / Kyoto.js 11 LT
Kyoto.js 11
http://kyotojs.connpass.com/event/39462/
Susisu
October 22, 2016
Tweet
Share
More Decks by Susisu
See All by Susisu
null or undefined
susisu
24
6.3k
Mackerel のフロントエンドフレームワーク移行 序章 / Hatena Engineer Seminar #13
susisu
0
2k
スクリーンショット撮影のために Puppeteer を操る / Kyoto.js 16
susisu
0
770
BuckleScript 使ってみた
susisu
0
270
Atom パッケージ開発のすゝめ
susisu
1
2.1k
5分でわかる Curry–Howard 同型対応
susisu
0
870
遅延評価と健康
susisu
0
580
楽しく学ぶ難解プログラミング言語
susisu
0
710
多分これが一番早いと思います
susisu
0
400
Other Decks in Programming
See All in Programming
令和トラベルにおけるLLM活用事例:社内ツール開発から得た学びと実践
ippo012
0
150
From Idea to IDE: Developing Plugins for Android Studio
thisaay
1
170
いつか使える ObjectSpace / Maybe useful ObjectSpace
euglena1215
2
130
オートマトン学習しろ / Do automata learning
makenowjust
3
130
GraphQL あるいは React における自律的なデータ取得について
quramy
11
2.9k
実践!難読化ガイド
mitchan
0
160
REXML改善のその後
naitoh
0
190
エンジニア1年目で複雑なコードの改善に取り組んだ話
mtnmr
3
2k
LangChainの現在とv0.3にむけて
os1ma
4
910
実践 Advanced CallKit 〜快適な通話の実現に向けて〜
mot_techtalk
3
140
Patched fetch did not work
quramy
3
180
Why Prism?
kddnewton
4
1.7k
Featured
See All Featured
How to Think Like a Performance Engineer
csswizardry
16
960
Git: the NoSQL Database
bkeepers
PRO
425
64k
Designing on Purpose - Digital PM Summit 2013
jponch
114
6.8k
Mobile First: as difficult as doing things right
swwweet
221
8.8k
How To Stay Up To Date on Web Technology
chriscoyier
786
250k
Building an army of robots
kneath
302
42k
The Power of CSS Pseudo Elements
geoffreycrofte
71
5.3k
Save Time (by Creating Custom Rails Generators)
garrettdimon
PRO
24
610
Imperfection Machines: The Place of Print at Facebook
scottboms
263
13k
Designing Experiences People Love
moore
138
23k
Code Reviewing Like a Champion
maltzj
517
39k
Documentation Writing (for coders)
carmenintech
65
4.3k
Transcript
δΣω Ϩ ʔ λ Λ ༗ ޮ ׆ ༻ ͠
ୂ 2 0 1 6 - 1 0 - 2 2 K y o t o . j s 1 1 Twitter @susisu2413 / GitHub @susisu
Q . δΣω Ϩ ʔ λ Կ ʹ
͑Δʁ
1 . ί ϧ ʔ νϯ
app.use(function* (next) { const start = new Date(); // (1)
yield next; const end = new Date(); // (3) // log (4) }); ! app.use(function* (next) { yield next; // respond (2) }); ྫ: Koa
2 . Ԇ Ϧε τ
function range(a, b, s = 1) { const arr =
[]; for (let n = a; n < b; n += s) { arr.push(n); } return arr; } ! for (const n of range(1, 10)) { doSomething(n); // from 1 to 9 }
function* xrange(a, b, s = 1) { for (let n
= a; n < b; n += s) { yield n; } } ! for (const n of xrange(1, 10)) { doSomething(n); // from 1 to 9 }
function* fibonacci() { let [a, b] = [1, 1]; while
(true) { yield a; [a, b] = [b, a + b]; } } ! for (const n of fibonacci()) { doSomething(n); // 1, 1, 2, 3, 5, ... }
3 . Π ς Ϩ ʔ λ ͷ Ճ
function* concat(iter1, iter2) { yield* iter1; yield* iter2; } !
for (const x of concat(arr1, arr2)) { doSomething(x); }
function* map(func, iter) { for (const x of iter) {
yield func(x); } } ! for (const n of map(n => n ** 2, arr)) { doSomething(n); }
4 . ඇ ಉ ظ ॲ ཧ
fetch().then(x => fetch().then(y => fetch().then(z => doSomething(x, y, z) )
) ); before (Promise)
co(function* () { const x = yield fetch(); const y
= yield fetch(); const z = yield fetch(); return doSomething(x, y, z); }); after (Promise + Generator + co)
Q . ଞ ʹ δΣω Ϩ ʔ λ ͕
͑Δ ໘ ͋ Δʁ
ͦ ͦ δΣω Ϩ ʔ λ ͱ
g e n . n e x t ( )
{ d o n e : f a l s
e , v a l u e : * } g e n . n e x t ( )
{ d o n e : f a l s
e , v a l u e : * } g e n . n e x t ( ) g e n . n e x t ( ) gen.next ͷதมΘ͍ͬͯΔ
{ d o n e : f a l s
e , v a l u e : * } { d o n e : f a l s e , v a l u e : * } g e n . n e x t ( ) g e n . n e x t ( ) g e n . n e x t ( )
{ d o n e : f a l s
e , v a l u e : * } { d o n e : f a l s e , v a l u e : * } { d o n e : t r u e , v a l u e : * } g e n . n e x t ( ) g e n . n e x t ( ) g e n . n e x t ( )
ݟํΛม͑Δͱ͍͔ʹԆϦετ d o n e : f a l s
e v a l u e ( ) = > d o n e : f a l s e v a l u e ( ) = > d o n e : t r u e v a l u e
d o n e : f a l s e
v a l u e x = > d o n e : f a l s e v a l u e y = > d o n e : t r u e v a l u e .next() ҾΛͱΕΔ
fetch().then(x => fetch().then(y => fetch().then(z => doSomething(x, y, z) )
) ); PromiseΛͬͨඇಉظॲཧ
None
d o n e : f a l s e
v a l u e x = > d o n e : f a l s e v a l u e y = > d o n e : t r u e v a l u e
t h e n v a l u e x
= > t h e n v a l u e y = > re s o l v e v a l u e .then() Ͱͭͳ͗߹ΘͤΔ
co(function* () { const x = yield fetch(); const y
= yield fetch(); const z = yield fetch(); return doSomething(x, y, z); }); Promise + Generator + co
Q . ଞ ʹ δΣω Ϩ ʔ λ ͕
͑Δ ໘ ͋ Δʁ
A . ͋ Γ · ͢
5 . ύ ʔ α ί ϯ Ϗω ʔ λ
symbol("(").bind(_ => expr.bind(x => symbol(")").bind(_ => pure(x) ) ) );
ׅހ (ʙ) ʹೖͬͨࣜͷύʔα
qo(function* () { yield symbol("("); const x = yield expr;
yield symbol(")"); return x; }); దͳؔΛ͑……
6 . * ద ͳ Ϟ φ υ ※
Ͳ ΕͰ ྑ ͍ ͱ ͍ ͏ Θ ͚ Ͱ ͳ ͍
δΣω Ϩ ʔ λ Λ ༗ ޮ ׆ ༻ ͠
ୂ ׆ ಈ ใ ࠂ
δΣω Ϩ ʔ λ Ԇ Ϧε τ Λ
Ұ ൠ Խ ͠ ͨ Α ͏ ͳ ͷ
· ͩ · ͩ ͑Δ ໘ ͕ ͋
Γ ͦ ͏ ྫ : ύ ʔ α ί ϯ Ϗω ʔ λ
ଞ ʹ ׆ ༻ ࣄ ྫ ͕ ͋ Ε
͓ ڭ ͑͘ ͩ ͞ ͍
{ d o n e : t r u e
, v a l u e : " T h a n k s " }