Debugger Statementについて

Debugger Statementの紹介と使い方
proposal-debugger-operandsについて

Transcript

1. Debugger
   Statement
   

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2. Name
   @brn (ꫬꅿ⨳ⵃ)
   Occupation
   ؿٗٝزؒٝسؒٝآص،٥ط؎ذ؍ـؒٝآص،
   Company
   Cyberagent ،سذؙأةآؔ AI Messenger
   OSS
   Contributor of V8
   About
   http://info.b6n.ch
   

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3. What is debugger?
   debugger statementהכ؝٦س⚥ח剅ֻֿהדرغحؖ׾饯⹛׃ـ
   ٖ؎ؙ׃גֻ׸׷堣腉
   

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4. const ret = foo()!
   if (ret) {!
   debugger;!
   }!
   

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6. In V8
   BytecodeהJIT؝٦سדⰟ鸐ךⳢ椚׾遤ֲ
   

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7. Bytecode
   DebuggerعٝسָٓDebuggerغ؎ز؝٦س׾鋅אֽ׷ה
   Runtime_HandleDebuggerStatement׾ㄎן⳿׃גծ✲⵸ח涫
   ꐮׁ׸גְ׷؝٦ٕغحؙ׾ㄎן⳿ׅ
   In V8
   

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8. JIT Code
   JIT⻉ך麓玎דㄏ⟀ך⽃秪⻉הְֲ剑黝⻉ָ遤׻׸׷ָծ׉ך麓
   玎דDebugger Statementכ⯓玎ך
   Runtime_HandleDebuggerStatementㄎן⳿׃ך؝٦سפה湫
   䱸㢌䳔ׁ׸׷
   In V8
   

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9. Break Point
   אְדזךדBreakpointחאְג
   ـٓؐؠך؎ٝألؙةַ׵䭷㹀ׅ׷ֿהָדֹ׷
   •  In V8
   

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11. In V8
    DebugBreakכDebugger Statementה麩׏גוֿח䯏Ⰵׁ׸׷ַ
    ׻ַ׵זְךד✲⵸חRuntime_HandleDebuggerStatementהַח
    כ㢌䳔דֹזְ
    

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12. Bytecode
    DebugBreakعٝسָٓDebug::HandleDebugBreak׾ㄎן⳿׃
    גծ穠卓Debugger StatementהずׄⳢ椚׾遤ֲ
    In V8
    

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13. JIT Code(X64)
    ـٖ؎ؙه؎ٝزכׅץגInt3ㄏ⟀ָ涪遤ׁ׸גSIGTRAP׾䒷ֹ
    饯ֿׅ
    interruptָ饯ֿ׷הStackGuard::HandleInterruptsָㄎן⳿ׁ׸
    גծ׉ַֿ׵Debug::HandleDebugBreakפ
    In V8
    

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14. Future
    ⯓傈ךTC39 Meetingדproposal-debugger-operandָStage1ח
    ז׏׋
    

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15. proposal-debugger-operand
    ـٖ؎ؙه؎ٝزךؚٕ٦ف⻉ח״׷♧俕ON/OFFծ勴⟝➰ֹـ
    ٖ؎ؙך鏣㹀瘝ָ遤ִ׷
    Future
    

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16. const log = (v) => {!
    debugger { group: 'logging' };!
    console.log(v);!
    };!
    

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17. const route = (httpRequest) => {!
    debugger {!
    test: () => httpRequest.tracing || !isProduction!
    };!
    console.log(v);!
    };!
    

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18. 㹋騧
    Ꟛ涪儗חכDebugger׾㙵׭鴥׿דծٔٔ٦أ儗ח嶊ׅ
    Webpack׾⢪׏ג׷ז׵Uglifyָ嶊׃גֻ׸׷
    v4ך㜥さכmode productionד⹧䩛ח嶊ִ׷
    

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19. class Logger {!
    fatal() {!
    console.error("Error");!
    debugger;!
    }!
    }!
    

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20. תה׭
    ⢪׏ג׷➂㼰זְ⽩韋דָׅꟚ涪儗ח⢪ֲה穠圓嚂דׅ
    

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