unicode

Summary

Returns a Boolean value indicating the state of the Unicode flag (u) used with a regular expression. Default is false. Read-only.

Syntax

regex.unicode

Examples

The following example illustrates the use of the Unicode property.

// https://mathiasbynens.be/notes/es6-unicode-regex#impact-dot
// Note: `𝌆` is U+1D306 TETRAGRAM FOR CENTRE, a supplementary Unicode symbol.
var string = 'a𝌆b';

console.log(/a.b/.unicode);
// → false

console.log(/a.b/.test(string));
// → false

console.log(/a.b/u.unicode);
// → true

console.log(/a.b/u.test(string));
// → true

var match = string.match(/a(.)b/u);
console.log(match[1]);
// → '𝌆'

View live example

Remarks

The unicode property returns true if the Unicode flag is set for a regular expression, and returns false if it is not.

The Unicode flag, when used, enables various Unicode-related features for regular expressions, such as the use of ES6 Unicode code point escapes (e.g. /\u{1D306}/u).

See also

Related articles

Javascript

• propertyName

• Number

• unicode

• future reserved words

Other articles

• global Property (Regular Expression)
• ignoreCase Property (Regular Expression)
• multiline Property (Regular Expression)
• sticky Property (Regular Expression)

External resources

• Unicode-aware regular expressions in ECMAScript 6
• regexpu – a source code transpiler that enables the use of ES6 Unicode regular expressions in ES5
• [Traceur REPL demo](https://google.github.io/traceur-compiler/demo/repl.html#%2F%2F%20Traceur%20now%20uses%20regexpu%20(https%3A%2F%2Fmths.be%2Fregexpu)%20to%20transpile%20regular%0A%2F%2F%20expression%20literals%20that%20have%20the%20ES6%20%60u%60%20flag%20set%20into%20equivalent%20ES5.%0A%0A%2F%2F%20Match%20any%20symbol%20from%20U%2B1F4A9%20PILE%20OF%20POO%20to%20U%2B1F4AB%20DIZZY%20SYMBOL.%0Avar%20regex%20%3D%20%2F%5B%F0%9F%92%A9-%F0%9F%92%AB%5D%2Fu%3B%20%2F%2F%20Or%2C%20%60%2F%5Cu%7B1F4A9%7D-%5Cu%7B1F4AB%7D%2Fu%60.%0Aconsole.log(%0A%20%20regex.test(‘%F0%9F%92%A8’)%2C%20%2F%2F%20false%0A%20%20regex.test(‘%F0%9F%92%A9’)%2C%20%2F%2F%20true%0A%20%20regex.test(‘%F0%9F%92%AA’)%2C%20%2F%2F%20true%0A%20%20regex.test(‘%F0%9F%92%AB’)%2C%20%2F%2F%20true%0A%20%20regex.test(‘%F0%9F%92%AC’)%20%20%2F%2F%20false%0A)%3B%0A%0A%2F%2F%20See%20https%3A%2F%2Fmathiasbynens.be%2Fnotes%2Fes6-unicode-regex%20for%20more%20examples%20and%0A%2F%2F%20info.%0A)