This script does not throw exception:

"".split(undefined,{valueOf:function(){throw 2}})

ECMA 15.5.4.14 String.prototype.split (separator, limit)

String.prototype.split steps are as follows:

1. Call CheckObjectCoercible passing the this value as its argument.

2. Let S be the result of calling ToString, giving it the this value as its argument.

3. Let A be a new array created as if by the expression new Array()where Array is the standard built-in constructor with that name.

4. Let lengthA be 0.

5. If limit is undefined, let lim = 232–1; else let lim = ToUint32(limit).

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