JavaScript: `new RegExp('hi')` versus `RegExp('hi')`? [duplicate]

问题

This question already has answers here:

JavaScript: using constructor without operator 'new' (2 answers)

Closed 4 years ago.

What is the difference between RegExp('hi') and new RegExp('hi')?

Does the new keyword do anything here?

回答1:

It is identical

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.

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

来源：https://stackoverflow.com/questions/39215710/javascript-new-regexphi-versus-regexphi