Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
The non-standard input property is a static property of regular expressions that contains the string against which a regular expression is matched. RegExp.$_ is an alias for this property.
Syntax
RegExp.input RegExp.$_
Description
The input property is static, it is not a property of an individual regular expression object. Instead, you always use it as RegExp.input or RegExp.$_.
The value of the input property is modified whenever the searched string on the regular expression is changed and that string is matching.
Examples
Using input and $_
var re = /hi/g;
re.test("hi there!");
RegExp.input; // "hi there!"
re.test("foo"); // new test, non-matching
RegExp.$_; // "hi there!"
re.test("hi world!"); // new test, matching
RegExp.$_; // "hi world!"
Specifications
Non-standard. Not part of any current specification.
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |
| Feature | Android | Chrome for Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|---|
| Basic support | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) | (Yes) |