syntax:

RegExp.input

description:

If no string is passed to RegExp exec() or to RegExp test(), then RegExp.input is used as the target string. To be used as the target string, it must be assigned a value. RegExp.input is equivalent to RegExp.$_, for compatibility with PERL.

Read/write property.

see:

RegExp exec(), RegExp test()

example:

var pat = /(t.o/;

RegExp.input = "one two three two one";

pat.exec();

   // "two" is matched