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 lastParen
property is a static and read-only property of regular expressions that contains the last parenthesized substring match, if any. RegExp.$+
is an alias for this property.
Description
The lastParen
property is static, it is not a property of an individual regular expression object. Instead, you always use it as RegExp.lastParen
or RegExp['$+']
.
The value of the lastParen
property is read-only and modified whenever a successful match is made.
You can not use the shorthand alias with the dot property accessor (RegExp.$+
), because the parser expects an expression with "+" in that case and a SyntaxError
is thrown. Use the bracket notation for property access.
Examples
Using lastParen and $+
var re = /(hi)/g; re.test('hi there!'); RegExp.lastParen; // "hi" RegExp['$+']; // "hi"
Specifications
Specification |
---|
Legacy RegExp features in JavaScript |
Browser compatibility
Desktop | Mobile | Server | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
RegExp.lastParen ($+ ) | Chrome Full support 1 | Edge Full support 12 | Firefox Full support 1 | IE Full support 5.5 | Opera Full support 10.5 | Safari Full support 3 | WebView Android Full support 1 | Chrome Android Full support 18 | Firefox Android Full support 4 | Opera Android Full support 11 | Safari iOS Full support 1 | Samsung Internet Android Full support 1.0 | nodejs Full support Yes |
Legend
- Full support
- Full support
- Non-standard. Expect poor cross-browser support.
- Non-standard. Expect poor cross-browser support.