问题
What is the benefit to using the ECMAScript 2016 exponentiation operator over the current Math.pow()? In other words, besides reducing key strokes, what is the difference between
Math.pow(2, 2) => 4 and 2 ** 2 => 4
回答1:
None. As you can read in the ES7 spec, both Math.pow and the ** exponentation operator cast their arguments/operands to numbers and use the very same algorithm to determine the result.
Addendum: this changed with the introduction of the BigInt type in ES2020, whose values are only supported by operators (including **) but not the Math object.
回答2:
Math.pow(2,2) === 2**2; // FALSE
Math.pow(99,99);
99 ** 99;
Result:
3.697296376497263e+197
3.697296376497268e+197
回答3:
Late to the party, as much as there is no difference between the two ways, I recently came to realize that the ** exponentiation operator isn't supported in Internet Explorer, so developers that are interested in cross-browser support for their applications may want to choose the Math.pow(...) over the exponentiation operator.
来源：https://stackoverflow.com/questions/37601189/difference-between-ecmascript-2016-exponentiation-operator-and-math-pow