JavaScript: `new RegExp(' hi' )` versus ` RegExp ('hi' )`?

Question

RegExp('hi') 和有什么区别和new RegExp('hi') ？

new 是吗？关键字在这里做什么？

Answer 1

完全相同

The RegExp constructor is the %RegExp% intrinsic object and the initial value of the RegExp property of the global object. When RegExp is called as a function rather than as a constructor, it creates and initializes a new RegExp object. Thus the function call RegExp(…) is equivalent to the object creation expression new RegExp(…) with the same arguments.

来自http://www.ecma-international.org/ecma-262/6.0/#sec-regexp-constructor