As it is currently written, the ‘esc’ function returns a string that must be passed into the instantiation call for RegExp. So you would want to do the following:

var r = new RegExp(RegExp.esc(str));

You could modify ‘esc’ to return the regular expression object, if you wanted to. However, I have written it this way so you can append to the escaped ’str’ before creating a new regular expression.

How is the best way to use the example 2 above? I am confused. I’m showing some tries below, by I believe there’s a better way.

try 1:
var r = new RegExp((new Regexp()).esc(str));

try 2:
var r = new RegExp(str); r.esc(str);

try 3:
var r = new RegExp(str); r.esc();

try 4:
var r = new RegExp.esc(str); // does this work?

I sincerely don’t believe I have to write RegExp or str twice.
I think it’s simpler to use one stand-alone function (not a method), say escapeRE():

var r = new RegExp(escapeRE(str));