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
Numbers in javascript
Search
Taketoshi Aono(青野健利 a.k.a brn)
February 26, 2018
Programming
1
5.6k
Numbers in javascript
JSのNumberについて
Taketoshi Aono(青野健利 a.k.a brn)
February 26, 2018
Tweet
Share
More Decks by Taketoshi Aono(青野健利 a.k.a brn)
See All by Taketoshi Aono(青野健利 a.k.a brn)
document.write再考
brn
6
3.1k
Parsing Javascript
brn
14
9.4k
JSON & Object Tips
brn
1
540
CA 1Day Youth Bootcamp for Frontend LT
brn
0
1k
Modern TypeScript
brn
2
850
javascript - behind the scene
brn
3
790
tc39 proposals
brn
0
950
プロダクト開発とTypeScript
brn
8
3k
React-Springでリッチなアニメーション
brn
1
750
Other Decks in Programming
See All in Programming
なるべく楽してバックエンドに型をつけたい!(楽とは言ってない)
hibiki_cube
0
140
フロントエンド開発の勘所 -複数事業を経験して見えた判断軸の違い-
heimusu
7
2.8k
Honoを使ったリモートMCPサーバでAIツールとの連携を加速させる!
tosuri13
1
180
Grafana:建立系統全知視角的捷徑
blueswen
0
330
Raku Raku Notion 20260128
hareyakayuruyaka
0
300
「ブロックテーマでは再現できない」は本当か?
inc2734
0
1k
React 19でつくる「気持ちいいUI」- 楽観的UIのすすめ
himorishige
11
7.4k
ノイジーネイバー問題を解決する 公平なキューイング
occhi
0
100
AWS re:Invent 2025参加 直前 Seattle-Tacoma Airport(SEA)におけるハードウェア紛失インシデントLT
tetutetu214
2
110
Amazon Bedrockを活用したRAGの品質管理パイプライン構築
tosuri13
5
730
Data-Centric Kaggle
isax1015
2
780
コントリビューターによるDenoのすゝめ / Deno Recommendations by a Contributor
petamoriken
0
200
Featured
See All Featured
For a Future-Friendly Web
brad_frost
182
10k
Taking LLMs out of the black box: A practical guide to human-in-the-loop distillation
inesmontani
PRO
3
2k
実際に使うSQLの書き方 徹底解説 / pgcon21j-tutorial
soudai
PRO
196
71k
The AI Revolution Will Not Be Monopolized: How open-source beats economies of scale, even for LLMs
inesmontani
PRO
3
3k
Why Your Marketing Sucks and What You Can Do About It - Sophie Logan
marketingsoph
0
76
Breaking role norms: Why Content Design is so much more than writing copy - Taylor Woolridge
uxyall
0
170
Beyond borders and beyond the search box: How to win the global "messy middle" with AI-driven SEO
davidcarrasco
1
53
Digital Projects Gone Horribly Wrong (And the UX Pros Who Still Save the Day) - Dean Schuster
uxyall
0
370
Build your cross-platform service in a week with App Engine
jlugia
234
18k
JavaScript: Past, Present, and Future - NDC Porto 2020
reverentgeek
52
5.8k
The Curse of the Amulet
leimatthew05
1
8.6k
Leo the Paperboy
mayatellez
4
1.4k
Transcript
Numbers in javascript
Name @brn (ꫬꅿ⨳ⵃ) Occupation ؿٗٝزؒٝسؒٝآص،٥ط؎ذ؍ـؒٝآص، Company Cyberagent ،سذؙأةآؔ AI Messenger
OSS Contributor of V8 About http://info.b6n.ch
Number ES2016~2018穗גjavascriptך侧⦼㘗ח ְֻאַ㢌⻉ָ֮ךדך鑧
Variations - 侭侧 - 㼭侧 - 16鹌侧 - 8鹌侧 -
2鹌侧 - Bigint - Separator
侭侧 64bitתדך侭侧䪔ִ ⰻ鿇涸חכ㹋鄲⣛㶷ָ31bit侭侧ה64bit Doubleדⴽגְծ 64bit Doubleך
㼭侧 㼭侧挿 הֻח鎉ֲֿהזְָծⰻ鿇涸חכ64bit DoubleדⳢ椚ׁ זךד鎘皾穠卓כ鵚⡂⦼חז
16鹌侧 0xדכׄת侧⦼ CSSהַדֶזׄ
8鹌侧 0oדכׄתַ 0~ד7⟃♳ך侧⦼ָזְ㜥さח8鹌侧חז ؿ؋؎ٕػ٦ىحءّٝהַדֶזׄ
// 8進数! 0o777! ! // 暗黙の8進数 0777! ! // 0から始まる10進数
0778! ! "use strict";! 0777 // Error!!
2鹌侧 0bַ㨣ת0ה1ך⢪欽〳腉זٔذٕٓ
// 2進数! 0b11101101 // 237!
BigInt 64bit⟃♳ך侧⦼䪔ֲ㜥さח⢪ֲ 植㖈Stage3 侧⦼ٔذٕٓך䖓ח n אֽֿהדBigIntٔذٕٓ邌植ׅկ HexװOctalٔذٕٓ؟ه٦زկ侧⦼ٔذٕٓהずֻׄn劣㽵ח אֽֿהדBigIntחזկ(׃ծOctalכ0oXXX䕎䒭ך) תծtypeof <bigint>כ
'bigint'ָ䨱կ
// Bigint! 10n + 10n // 20n! 10n + 10
// Error! typeof 10n // 'bigint'! BigInt('100') // 100n!
BigInt 鑫׃ֻכ https://speakerdeck.com/brn/ecmascript-bigint ח剅ְ
Separator 植㖈Stage3 תmergeׁגְזְָV8ח㹋鄲׃ג ךֲ⢪ִ״ֲחזծ✮㹀
// Numeric Separators! 1_0_0_0_0! 0xFF_FF_FF! 0b1000_1111_0000! 0o7_7_7! ! 1__0 //
Error! 1000_ // Error!
׀幠耮ָ֮הֲ׀ְׂת׃