譛ャ鬆√�逶ョ谺。 逶ョ谺。 谺。鬆�: 15-8_The_Math_Object 蜑埼��: 15-6_Boolean_Objects
繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ァ縺ッ縺ェ縺城未謨ー縺ィ縺励※蜻シ蜃コ縺輔l繧� Number 縺ッ縲∝梛螟画鋤繧定。後≧縲�
value 縺御セ帷オヲ縺輔l繧後� ToNumber(value) 縺ォ繧医j邂怜�縺励◆ (Number 繧ェ繝悶ず繧ァ繧ッ繝医〒縺ッ縺ェ縺�) 謨ー蛟、繧定ソ斐@縲∽セ帷オヲ縺輔l縺ェ縺代l縺ー +0 繧定ソ斐☆縲�
new
蠑上�荳驛ィ縺ィ縺励※蜻シ蜃コ縺輔l繧� Number 縺ッ繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ァ縺ゅk: 譁ー隕上↓逕滓�縺励◆繧ェ繝悶ず繧ァ繧ッ繝医r蛻晄悄蛹悶☆繧九�
譁ー隕上↓讒狗ッ峨&繧後◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Prototype]] 繝励Ο繝代ユ繧」縺ッ縲� Number.prototype (繧サ繧ッ繧キ繝ァ繝ウ 15.7.3.1) 縺ョ蛻晄悄蛟、縺ァ縺ゅk縲√が繝ェ繧ク繝翫Ν縺ョ Number 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝医↓險ュ螳壹&繧後k縲�
譁ー隕上↓讒狗ッ峨&繧後◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Class]] 繝励Ο繝代ユ繧」縺ッ縲� "Number" 縺ォ險ュ螳壹&繧後k縲�
譁ー隕上↓讒狗ッ峨&繧後◆繧ェ繝悶ず繧ァ繧ッ繝医� [[Value]] 繝励Ο繝代ユ繧」縺ッ縲� value 縺御セ帷オヲ縺輔l繧九↑繧峨� ToNumber(value) 縺ォ縲√◎縺�〒縺ェ縺代l縺ー +0 縺ォ險ュ螳壹&繧後k縲�
Number 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� (繧サ繧ッ繧キ繝ァ繝ウ 15.3.4) 縺ァ縺ゅ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� Number 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、:
Number.prototype 縺ョ蛻晄悄蛟、縺ッ Number 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 15.7.4) 縺ァ縺ゅk縲�
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�
Number.MAX_VALUE 縺ョ蛟、縺ッ縲¨umber 蝙九�豁」縺ョ譛蛾剞謨ー縺ョ譛螟ァ蛟、縺ァ縺ゅj縲√♀縺翫h縺� 1.7976931348623157 テ� 10308 縺ァ縺ゅk縲�
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ{ DontEnum, DontDelete, ReadOnly } 繧呈戟縺、縲�
Number.MIN_VALUE 縺ョ蛟、縺ッ Number 蝙九�豁」縺ョ譛蟆丞、縺ァ縺ゅj縲√♀縺翫h縺� 5 テ� 10-324.
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�
Number.NaN 縺ョ蛟、縺ッ NaN 縺ァ縺ゅk縲�
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�
Number.NEGATIVE_INFINITY 縺ョ蛟、縺ッ縲� -竏� 縺ァ縺ゅk縲�
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�
Number.POSITIVE_INFINITY 縺ョ蛟、縺ッ縲� +竏� 縺ァ縺ゅk縲�
縺薙�繝励Ο繝代ユ繧」縺ッ縲∝ア樊ァ { DontEnum, DontDelete, ReadOnly } 縺ァ縺ゅk縲�
Number 繝励Ο繝医ち繧、繝励が繝悶ず繧ァ繧ッ繝� 縺ッ縲√◎繧瑚�霄ォ 蛟、縺� +0 縺ョ Number 繧ェ繝悶ず繧ァ繧ッ繝� ([[Class]] 縺� "Number") 縺ァ縺ゅk縲�
Number 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、縺ッ縲� 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 15.2.3.1) 縺ァ縺ゅk縲�
莉・髯阪� Number 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」縺ァ縺ゅk髢「謨ー縺ョ隱ャ譏弱↓縺翫>縺ヲ縲√ヵ繝ャ繝シ繧コ "縺薙� Number 繧ェ繝悶ず繧ァ繧ッ繝�" 縺ッ縲�未謨ー縺ョ蜻シ蜃コ縺励↓縺ィ縺」縺ヲ縺ョ this
蛟、縺ァ縺ゅk繧ェ繝悶ず繧ァ繧ッ繝医r蜿ら�縺吶k; this
蛟、縺後が繝悶ず繧ァ繧ッ繝医〒縺ッ縺ェ縺上∝�驛ィ [[Class]] 繝励Ο繝代ユ繧」縺ョ蛟、縺� "Number" 縺ェ繧峨�縲∽セ句、� TypeError 縺梧兜縺偵i繧後k縲� 縺セ縺溘√ヵ繝ャ繝シ繧コ "縺薙�謨ー蛟、" 縺ッ縲√%縺ョ Number 繧ェ繝悶ず繧ァ繧ッ繝医〒縺ゅi繧上&繧後k謨ー蛟、縲√▽縺セ繧翫√%縺ョ Number object 縺ョ蜀�Κ [[Value]] 繝励Ο繝代ユ繧」縺ョ蛟、繧貞盾辣ァ縺吶k縲�
Number.prototype.constructor 縺ョ蛻晄悄蛟、縺ッ縲∫オ�セシ縺ソ Number 繧ウ繝ウ繧ケ繝医Λ繧ッ繧ソ縺ァ縺ゅk縲�
radix 縺梧焚 10 縺セ縺溘� undefined 縺ェ繧峨�縲√%縺ョ謨ー蛟、縺ッ蠑墓焚縺ィ縺励※ ToString 貍皮ョ怜ュ舌↓荳弱∴繧峨l繧�; 邨先棡縺ョ譁�ュ怜�蛟、縺瑚ソ斐&繧後k縲�
radix 縺� 2 縺九i 36 縺ョ謨エ謨ー縺ァ縲� 10 縺ァ縺ェ縺�↑繧峨�縲∫オ先棡縺ッ譁�ュ怜�縺ァ縲∝ョ溯」�セ晏ュ倥�驕ク謚槭→縺ェ繧九�
toString
髢「謨ー縺ッ豎守畑逧�〒縺ッ縺ェ縺�; this
蛟、縺� Number 繧ェ繝悶ず繧ァ繧ッ繝医〒縺ェ縺代l縺ー縲∽セ句、� TypeError 繧呈兜縺偵k縲ゅ◎繧後f縺医∽サ悶�遞ョ鬘槭�繧ェ繝悶ず繧ァ繧ッ繝医↓繝。繧ス繝�ラ縺ィ縺励※霆「逕ィ縺ァ縺阪↑縺��
繝帙せ繝育腸蠅��迴セ蝨ィ縺ョ繝ュ繧ア繝シ繝ォ縺ョ諷」鄙偵↓豐ソ縺」縺ヲ謨エ蠖「縺輔l繧� Number 縺ョ蛟、繧定。ィ縺呎枚蟄怜�蛟、繧堤函謌舌☆繧九ゅ%縺ョ髢「謨ー縺ッ螳溯」�セ晏ュ倥〒縲� toString 縺ィ蜷後§繧ゅ�繧定ソ斐☆縺薙→繧定ィア蜿ッ縺輔l縺ヲ縺�k縺梧耳螂ィ繧ゅ&繧後↑縺��
NOTE 縺薙�髢「謨ー縺ョ隨ャ荳繝代Λ繝。繝シ繧ソ縺ッ縲√%縺ョ讓呎コ悶�蟆�擂縺ョ繝舌�繧ク繝ァ繝ウ縺ァ菴ソ逕ィ縺輔l繧句庄閭ス諤ァ縺後≠繧�; 螳溯」��縺薙�繝代Λ繝。繝シ繧ソ繧剃サ悶�逕ィ騾斐↓菴ソ逕ィ縺励↑縺�%縺ィ繧呈耳螂ィ縺吶k縲�
縺薙�謨ー蛟、繧定ソ斐☆縲�
valueOf
髢「謨ー縺ッ豎守畑逧�〒縺ッ縺ェ縺�; this
蛟、縺� Number 繧ェ繝悶ず繧ァ繧ッ繝医〒縺ェ縺代l縺ー縲∽セ句、� TypeError 繧呈兜縺偵k縲ゅ◎繧後f縺医∽サ悶�遞ョ鬘槭�繧ェ繝悶ず繧ァ繧ッ繝医↓繝。繧ス繝�ラ縺ィ縺励※霆「逕ィ縺ァ縺阪↑縺��
蟆乗焚轤ケ縺ョ蠕後� fractionDigits 蛟九�謨ー蟄励↓縺」縺ヲ謨ー繧貞崋螳夂せ陦ィ險� (fixed-point notation) 縺吶k譁�ュ怜�繧定ソ斐☆縲� fractionDigits 縺� undefined 縺ェ繧峨�縲� 0 縺御サョ螳壹&繧後k縲� 蜈キ菴鍋噪縺ォ縺ッ縲∵ャ。縺ョ繧ケ繝�ャ繝励r螳溯。後☆繧�:
toFixed
繝。繧ス繝�ラ縺ョ length 繝励Ο繝代ユ繧」縺ッ 1 縺ァ縺ゅk縲�
toFixed
繝。繧ス繝�ラ縺後� 2 蛟倶サ・荳翫�蠑墓焚縺ァ蜻シ蜃コ縺輔l繧九↑繧峨�縲∵険繧玖�縺��譛ェ螳夂セゥ縺ァ縺ゅk (繧サ繧ッ繧キ繝ァ繝ウ 15 蜿ら�)縲�
螳溯」��縲� 0 譛ェ貅繧� 20 繧医j螟ァ縺阪> fractionDigits 縺ョ蛟、縺ォ蟇セ縺吶k toFixed
縺ョ謖ッ繧玖�縺��諡。蠑オ繧定ィア蜿ッ縺輔l繧九ゅ%縺ョ蝣エ蜷医� toFixed
縺ッ縺昴�繧医≧縺ェ蛟、縺ォ蟇セ縺� RangeError 繧呈兜縺偵k蠢�ヲ√�縺ェ縺��
NOTE toFixed
縺ョ蜃コ蜉帙�縲∝、縺ォ繧医▲縺ヲ縺ッ toString 繧医j豁」遒コ縺ァ繧医¥縲√◎繧後� toString 縺碁團謗・縺励◆謨ー蛟、縺九i謨ー繧貞玄蛻・縺吶k縺ョ縺ォ蜊∝�縺ェ譯∵焚繧貞�蜉帙☆繧九□縺代□縺九i縺ァ縺ゅk縲ゆセ九∴縺ー縲� (1000000000000000128).toFixed
(0) 縺� "1000000000000000128" 繧定ソ斐☆荳譁ケ縺ァ縲� (1000000000000000128).toString() 縺ッ "1000000000000000100" 繧定ソ斐☆縲�
1 蛟九�謨ー蟄励∝ー乗焚轤ケ縲� fractionDigits 蛟九�謨ー蟄励↓繧医▲縺ヲ謨ー繧呈欠謨ー陦ィ險倥☆繧区枚蟄怜�繧定ソ斐☆縲� fractionDigits 縺� undefined 縺ェ繧峨�縲∵焚繧剃ク諢上↓迚ケ螳壹☆繧九�縺ォ蠢�ヲ√→縺吶k縺ョ縺ィ蜷後§譯∵焚繧貞性繧 (縺薙�蝣エ蜷医∵焚縺梧欠謨ー陦ィ險倥〒蟶ク縺ォ蜃コ蜉帙&繧後k轤ケ繧帝勁縺� ToString 縺ォ莨シ縺ヲ縺�k)縲� 蜈キ菴鍋噪縺ォ縺ッ縲∵ャ。縺ョ繧ケ繝�ャ繝励r螳溯。後☆繧�:
toExponential
繝。繧ス繝�ラ縺ョ length 繝励Ο繝代ユ繧」縺ッ 1 縺ァ縺ゅk縲�
toExponential
繝。繧ス繝�ラ縺� 2 蛟倶サ・荳翫�蠑墓焚縺ァ蜻シ蜃コ縺輔l繧九↑繧峨�縲√◎縺ョ謖ッ繧玖�縺��譛ェ螳夂セゥ縺ァ縺ゅk (繧サ繧ッ繧キ繝ァ繝ウ 15 蜿ら�)縲�
螳溯」��縲� fractionDigits 縺� 0 繧医j蟆上&縺��エ蜷医√∪縺� 20 繧医j螟ァ縺阪>蝣エ蜷医� toExponential
縺ョ謖ッ繧玖�縺��諡。蠑オ繧定ィア蜿ッ縺輔l繧九ゅ%縺ョ蝣エ蜷� toExponential
縺ッ縺昴�蛟、縺ォ萓句、� RangeError 繧呈兜縺偵k蠢�ヲ√�縺ェ縺��
NOTE 荳願ィ倥�隕丞援縺ョ隕∵アゅh繧翫b繧医j邊セ蟇�↑蜿悶j豎コ繧√r謠蝉セ帙☆繧句ョ溯」�↓縺、縺�※縺ッ縲√せ繝�ャ繝� 19 縺ョ谺。縺ョ莉」譖ソ繝舌�繧ク繝ァ繝ウ繧偵ぎ繧、繝峨Λ繧、繝ウ縺ィ縺励※逕ィ縺�k縺薙→繧呈耳螂ィ縺吶k:
e, n, f 繧偵� f ≥ 0, 10f ≤ n < 10f+1, n × 10e-f 縺ョ謨ー蛟、縺� x, 縺九▽, 蜿ッ閭ス縺ェ髯舌j蟆上&縺� f 縺ァ縺ゅk繧医≧縺ェ謨エ謨ー縺ィ縺吶k縲り、�焚縺ョ n 縺悟ュ伜惠蜿ッ閭ス縺ァ縺ゅl縺ー縲� n × 10e-f 縺� x 縺ョ蛟、縺ォ譛繧りソ代>繧医≧縺ェ n 縺ョ蛟、繧帝∈謚槭☆繧九ょ庄閭ス縺ェ n 縺ョ蛟、縺� 2 蛟九≠繧後�縲∝�謨ー縺ァ縺ゅk譁ケ繧帝∈謚槭☆繧九�
1 蛟九�謨ー蟄励∝ー乗焚轤ケ縲� precision-1 蛟九�謨ー蟄励↓繧医k謖�焚陦ィ險倥√∪縺溘� precision 譯√�謨ー蟄励↓繧医k蝗コ螳夂せ陦ィ險倥�荳譁ケ縺ァ縺ゅi繧上&繧後k謨ー繧貞性繧譁�ュ怜�繧定ソ斐☆縲� precision 縺� undefined 縺ェ繧峨�縲∽サ」繧上j縺ォ ToString (繧サ繧ッ繧キ繝ァ繝ウ 9.8.1) 繧貞他蜃コ縺吶ょ�菴鍋噪縺ォ縺ッ縲∵ャ。縺ョ繧ケ繝�ャ繝励r螳溯。後☆繧�:
toPrecision
繝。繧ス繝�ラ縺ョ length 繝励Ο繝代ユ繧」縺ッ 1 縺ァ縺ゅk縲�
toPrecision
繝。繧ス繝�ラ縺� 2 蛟倶サ・荳翫�蠑墓焚縺ァ蜻シ蜃コ縺輔l繧九↑繧峨�縲√◎縺ョ謖ッ繧玖�縺��譛ェ螳夂セゥ縺ァ縺ゅk (繧サ繧ッ繧キ繝ァ繝ウ 15 蜿ら�)縲�
螳溯」��縲� precision 縺ョ蛟、縺� 0 繧医j蟆上&縺��エ蜷医√∪縺� 21 繧医j螟ァ縺阪>蝣エ蜷医� toPrecision
縺ョ謖ッ繧玖�縺��諡。蠑オ繧定ィア蜿ッ縺輔l繧九ゅ%縺ョ蝣エ蜷� toPrecision
縺ッ縺昴�蛟、縺ォ萓句、� RangeError 繧呈兜縺偵k蠢�ヲ√�縺ェ縺��
Number 繧、繝ウ繧ケ繧ソ繝ウ繧ケ縺ッ縲¨umber 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↓迚ケ縺ォ繝励Ο繝代ユ繧」繧呈戟縺溘↑縺��