譛ャ鬆√�逶ョ谺。 逶ョ谺。

15.2 Object 繧ェ繝悶ず繧ァ繧ッ繝�

15.2.1 髢「謨ー縺ィ縺励※蜻シ蜃コ縺輔l繧� Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ

繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ィ縺励※縺ァ縺ッ縺ェ縺城未謨ー縺ィ縺励※蜻シ蜃コ縺輔l繧� Object 縺ッ縲∝梛螟画鋤繧定。後≧縲�

15.2.1.1 Object ( [ value ] )

Object 髢「謨ー縺悟シ墓焚辟。縺励€√∪縺溘�蠑墓焚蛟、荳€縺、縺ァ蜻シ蜃コ縺輔l繧九→縺阪€∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. value 縺� null, undefined 縺ァ縺ゅk縺倶セ帷オヲ縺輔l縺ェ縺�→縺阪€∝宍蟇�↓繧ェ繝悶ず繧ァ繧ッ繝医さ繝ウ繧ケ繝医Λ繧ッ繧ソ縺悟酔縺伜シ墓焚 (繧サ繧ッ繧キ繝ァ繝ウ 15.2.2.1) 縺ァ蜻シ蜃コ縺輔l縺ヲ縺�k縺ェ繧峨�縲∵眠隕� Object 繧ェ繝悶ず繧ァ繧ッ繝医r逕滓�縺励※霑斐☆縲�
  2. ToObject(value) 繧定ソ斐☆縲�

15.2.2 Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ

Object 縺� new 蠑上�荳€驛ィ縺ィ縺励※蜻シ蜃コ縺輔l繧九→縺阪€√さ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ッ繧ェ繝悶ず繧ァ繧ッ繝医r菴懈�縺ァ縺阪k縲�

15.2.2.1 new Object ( [ value ] )

Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺悟シ墓焚縺ェ縺励€√∪縺溘�蠑墓焚 value 荳€縺、縺ァ蜻シ蜃コ縺輔l繧句�エ蜷医€∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. value 縺梧署萓帙&繧後↑縺代l縺ー縲√せ繝�ャ繝� 8 縺ク縲�
  2. value 縺ョ蝙九′ Object 縺ァ縺ェ縺代l縺ー縲√せ繝�ャ繝� 5 縺ク縲�
  3. value 縺� Native ECMAScript 繧ェ繝悶ず繧ァ繧ッ繝医↑繧峨�縲∵眠隕上↓繧ェ繝悶ず繧ァ繧ッ繝医r逕滓�縺帙★縲∝腰縺ォ value 繧定ソ斐☆縲�
  4. value 縺� Host 繧ェ繝悶ず繧ァ繧ッ繝医↑繧峨�縲?ost 繧ェ繝悶ず繧ァ繧ッ繝医↓繧医k螳溯」�セ晏ュ倥�譁ケ豕輔〒蜍穂ス懊@縲∫オ先棡縺瑚ソ斐&繧後k縲�
  5. value 縺ョ蝙九′ String 縺ェ繧峨�縲� ToObject(value) 繧定ソ斐☆縲�
  6. value 縺ョ蝙九′ Boolean 縺ェ繧峨�縲� ToObject(value) 繧定ソ斐☆縲�
  7. value 縺ョ蝙九′ Number 縺ェ繧峨�縲� ToObject(value) 繧定ソ斐☆縲�
  8. (蠑墓焚 value 縺梧署萓帙&繧後↑縺�€√∪縺溘�縺昴�蝙九′ Null 縺セ縺溘� Undefined 縺ァ縺ゅk縲�)
  9. Native ECMAScript 繧ェ繝悶ず繧ァ繧ッ繝医r逕滓�縺吶k縲�
  10. 譁ー隕上↓逕滓�縺励◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Prototype]] 繝励Ο繝代ユ繧」繧� Object prototype 繧ェ繝悶ず繧ァ繧ッ繝医↓險ュ螳壽眠隕上↓逕滓�縺励◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Class]] 繝励Ο繝代ユ繧」繧� "Object" 縺ォ險ュ螳壹☆繧九€�
  11. 譁ー隕上↓逕滓�縺励◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Value]] 繝励Ο繝代ユ繧」繧呈戟縺溘↑縺�€�
  12. 譁ー隕上↓逕滓�縺励◆ Native 繧ェ繝悶ず繧ァ繧ッ繝医r霑斐☆縲�

15.2.3 Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ョ繝励Ο繝代ユ繧」

Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ョ蜀�Κ [[Prototype]] 繝励Ο繝代ユ繧」縺ョ蛟、縺ッ縲� Function 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝医〒縺ゅk縲�

蜀�Κ繝励Ο繝代ユ繧」縺ィ length 繝励Ο繝代ユ繧」 (蛟、縺ッ 1) 縺ョ莉悶↓縲� Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ッ谺。縺ョ繝励Ο繝代ユ繧」繧呈戟縺、:

15.2.3.1 Object.prototype

Object.prototype 縺ョ蛻晄悄蛟、縺ッ Object 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝� (繧サ繧ッ繧キ繝ァ繝ウ 15.2.4) 縺ァ縺ゅk縲�

縺薙�繝励Ο繝代ユ繧」縺ッ螻樊€ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�

15.2.4 Object 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝医�繝励Ο繝代ユ繧」

Obuject 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝医�蜀�Κ [[Prototype]] 繝励Ο繝代ユ繧」縺ョ蛟、縺ッ null 縺ァ縺ゅj縲∝�驛ィ [[Class]] 繝励Ο繝代ユ繧」縺ョ蛟、縺ッ "Object" 縺ァ縺ゅk縲�

15.2.4.1 Object.prototype.constructor

Object.prototype.constructor 縺ョ蛻晄悄蛟、縺ッ縲∫オ�セシ縺ソ Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ァ縺ゅk縲�

15.2.4.2 Object.prototype.toString ( )

toString 繝。繧ス繝�ラ縺悟他蜃コ縺輔l繧九→縲∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. 縺薙�繧ェ繝悶ず繧ァ繧ッ繝医� [[Class]] 繝励Ο繝代ユ繧」繧貞叙蠕励€�
  2. 3 縺、縺ョ譁�ュ怜� "[object ", Result(1), "]" 繧帝€」邨舌@縺滓枚蟄怜�繧堤ョ怜�縺吶k縲�
  3. Result(2) 繧定ソ斐☆縲�

15.2.4.3 Object.prototype.toLocaleString ( )

縺薙�髢「謨ー縺ッ toString() 蜻シ蜃コ縺励�邨先棡繧定ソ斐☆縲�

NOTE 縺薙�髢「謨ー縺ッ縲∝�縺ヲ縺ョ Object 縺ォ縺昴l縺悟茜逕ィ縺ァ縺阪↑縺��エ蜷医〒繧ゆク€闊ャ逧�↑ toLocaleString 繧、繝ウ繧ソ繝シ繝輔ぉ繧、繧ケ繧剃ク弱∴繧九◆繧√↓謠蝉セ帙&繧後k縲ら樟蝨ィ縲� Array, Number, Date 縺後Ο繧ア繝シ繝ォ縺ォ蜿榊ソ懊☆繧狗峡閾ェ縺ョ toLocaleString 繝。繧ス繝�ラ繧呈署萓帙☆繧九€�

NOTE 縺薙�髢「謨ー縺ョ譛€蛻昴�繝代Λ繝。繝シ繧ソ縺ッ縲√%縺ョ讓呎コ悶�蟆�擂縺ョ繝舌�繧ク繝ァ繝ウ縺ォ縺翫>縺ヲ菴ソ逕ィ縺輔l縺昴≧縺ァ縺ゅk; 螳溯」��縺薙�繝代Λ繝。繝シ繧ソ菴咲スョ繧剃サ悶�譁ケ騾斐↓菴ソ逕ィ縺励↑縺�%縺ィ繧呈耳螂ィ縺吶k縲�

15.2.4.4 Object.prototype.valueOf ( )

valueOf 繝。繧ス繝�ラ縺ッ縺昴� this 蛟、繧定ソ斐☆縲ゅ%縺ョ繧ェ繝悶ず繧ァ繧ッ繝医′ host 繧ェ繝悶ず繧ァ繧ッ繝� (繧サ繧ッ繧キ繝ァ繝ウ15.2.2.1) 縺ョ Object 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ョ蜻シ縺ウ蜃コ縺励�邨先棡縺ァ縺ゅl縺ー縲∵悽譚・繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ォ貂。縺輔l縺� host 繧ェ繝悶ず繧ァ繧ッ繝医�繧医≧縺ォ valueOf 縺� this 蛟、繧定ソ斐☆縺倶サ悶�蛟、繧定ソ斐☆縺九�螳溯」�セ晏ュ倥〒縺ゅk縲�

15.2.4.5 Object.prototype.hasOwnProperty (V)

hasOwnProperty 繝。繧ス繝�ラ縺悟シ墓焚 V 縺ァ蜻シ蜃コ縺輔l繧九→縺阪€∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. O 繧� this 繧ェ繝悶ず繧ァ繧ッ繝医→縺吶k縲�
  2. ToString(V) 繧貞他蜃コ縺吶€�
  3. O 縺� Result(2) 縺ァ荳弱∴繧峨l繧句錐蜑阪�繝励Ο繝代ユ繧」繧呈戟縺溘↑縺代l縺ー縲� false 繧定ソ斐☆縲�
  4. true 繧定ソ斐☆縲�

NOTE [[HasProperty]] (繧サ繧ッ繧キ繝ァ繝ウ 8.6.2.4)縺ィ縺ッ逡ー縺ェ繧翫€√%縺ョ繝。繧ス繝�ラ縺ッ繝励Ο繝医ち繧、繝励メ繧ァ繝シ繝ウ繧定€��縺励↑縺�€�

15.2.4.6 Object.prototype.isPrototypeOf (V)

isPrototypeOf 繝。繧ス繝�ラ縺悟シ墓焚 V 縺ァ蜻シ蜃コ縺輔l繧九→縺阪€∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. O 繧� this 繧ェ繝悶ず繧ァ繧ッ繝医→縺吶k縲�
  2. V 縺後が繝悶ず繧ァ繧ッ繝医〒縺ェ縺代l縺ー縲� false 繧定ソ斐☆縲�
  3. V 繧� V 縺ョ [[Prototype]] 繝励Ο繝代ユ繧」縺ョ蛟、縺ィ縺吶k縲�
  4. V 縺� null 縺ェ繧峨�縲� false 繧定ソ斐☆縲�
  5. O 縺ィ V 縺悟酔縺倥が繝悶ず繧ァ繧ッ繝医r蜿ら�縺励※縺�k縲√∪縺溘�縺昴l繧峨′莠偵>縺ォ邨仙粋縺励◆繧ェ繝悶ず繧ァ繧ッ繝� (繧サ繧ッ繧キ繝ァ繝ウ 13.1.2) 繧貞盾辣ァ縺励※縺�k縺ェ繧峨�縲� true 繧定ソ斐☆縲�
  6. 繧ケ繝�ャ繝� 3 縺ク縲�

15.2.4.7 Object.prototype.propertyIsEnumerable (V)

propertyIsEnumerable 繝。繧ス繝�ラ縺悟シ墓焚 V 縺ァ蜻シ蜃コ縺輔l繧九→縺阪€∵ャ。縺ョ繧ケ繝�ャ繝励′蜿悶i繧後k:

  1. O 繧� this 縺ィ縺吶k縲�
  2. ToString(V) 繧貞他蜃コ縺吶€�
  3. O 縺� Result(2) 縺ァ荳弱∴繧峨l繧句錐蜑阪�繝励Ο繝代ユ繧」繧偵b縺溘↑縺代l縺ー縲� false 繧定ソ斐☆縲�
  4. 縺昴�繝励Ο繝代ユ繧」縺� DontEnum 螻樊€ァ繧呈戟縺」縺ヲ縺�l縺ー縲� false 繧定ソ斐☆縲�
  5. true 繧定ソ斐☆縲�

NOTE 縺薙�繝。繧ス繝�ラ縺ッ繝励Ο繝医ち繧、繝励メ繧ァ繝シ繝ウ繧定€��縺励↑縺�€�

15.2.5 Object 繧、繝ウ繧ケ繧ソ繝ウ繧ケ縺ョ繝励Ο繝代ユ繧」

Object 繧、繝ウ繧ケ繧ソ繝ウ繧ケ縺ッ縲� Object 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝医°繧臥カ呎価縺吶k繝励Ο繝代ユ繧」縺ョ荳翫↓迚ケ蛻・縺ェ繝励Ο繝代ユ繧」繧呈戟縺溘↑縺�€�

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