Number(), BigInt()は空の文字列を入れると0を返す

Number(), BigInt()は空の文字列を入れると0を返す．

Number("1")
>> 1
Number("a")
>> NaN
Number()
>> 0
Number("")
>> 0

BigInt("1")
>> 1n
BigInt("a")
>> VM105:1 Uncaught SyntaxError: Cannot convert a to a BigInt
    at BigInt (<anonymous>)
    at <anonymous>:1:1
BigInt()
>> Uncaught TypeError: Cannot convert undefined to a BigInt
    at BigInt (<anonymous>)
    at <anonymous>:1:1
BigInt("")
>> 0n

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