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Numbers in javascript
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Taketoshi Aono(青野健利 a.k.a brn)
February 26, 2018
Programming
1
5.4k
Numbers in javascript
JSのNumberについて
Taketoshi Aono(青野健利 a.k.a brn)
February 26, 2018
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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׃