XRegExp 4.4.0-32

XRegExp provides augmented (and extensible) JavaScript regular expressions. You get modern syntax and flags beyond what browsers support natively. XRegExp is also a regex utility belt with tools to make your grepping and parsing easier, while freeing you from regex cross-browser inconsistencies and other annoyances.

XRegExp supports all native ES6 regular expression syntax. It supports ES5+ browsers, and you can use it with Node.js or as a RequireJS module.

Performance

XRegExp compiles to native RegExp objects. Therefore regexes built with XRegExp perform just as fast as native regular expressions. There is a tiny extra cost when compiling a pattern for the first time.

Usage examples

// Using named capture and flag x for free-spacing and line comments
const date = XRegExp(
    `(?<year>  [0-9]{4} ) -?  # year
     (?<month> [0-9]{2} ) -?  # month
     (?<day>   [0-9]{2} )     # day`, 'x');

// XRegExp.exec gives you named backreferences on the match result
let match = XRegExp.exec('2017-02-22', date);
match.year; // -> '2017'

// It also includes optional pos and sticky arguments
let pos = 3;
const result = [];
while (match = XRegExp.exec('<1><2><3>4<5>', /<(\d+)>/, pos, 'sticky')) {
    result.push(match[1]);
    pos = match.index + match[0].length;
}
// result -> ['2', '3']

// XRegExp.replace allows named backreferences in replacements
XRegExp.replace('2017-02-22', date, '$<month>/$<day>/$<year>');
// -> '02/22/2017'
XRegExp.replace('2017-02-22', date, (match) => {
    return `${match.month}/${match.day}/${match.year}`;
});
// -> '02/22/2017'

// XRegExps compile to RegExps and work perfectly with native methods
date.test('2017-02-22');
// -> true

// The only caveat is that named captures must be referenced using
// numbered backreferences if used with native methods
'2017-02-22'.replace(date, '$2/$3/$1');
// -> '02/22/2017'

// Use XRegExp.forEach to extract every other digit from a string
const evens = [];
XRegExp.forEach('1a2345', /\d/, (match, i) => {
    if (i % 2) evens.push(+match[0]);
});
// evens -> [2, 4]

// Use XRegExp.matchChain to get numbers within <b> tags
XRegExp.matchChain('1 <b>2</b> 3 <B>4 \n 56</B>', [
    XRegExp('(?is)<b>.*?</b>'),
    /\d+/
]);
// -> ['2', '4', '56']

// You can also pass forward and return specific backreferences
const html =
    `<a href="http://xregexp.com/">XRegExp</a>
     <a href="http://www.google.com/">Google</a>`;
XRegExp.matchChain(html, [
    {regex: /<a href="([^"]+)">/i, backref: 1},
    {regex: XRegExp('(?i)^https?://(?<domain>[^/?#]+)'), backref: 'domain'}
]);
// -> ['xregexp.com', 'www.google.com']

// Merge strings and regexes, with updated backreferences
XRegExp.union(['m+a*n', /(bear)\1/, /(pig)\1/], 'i', {conjunction: 'or'});
// -> /m\+a\*n|(bear)\1|(pig)\2/i

These examples give the flavor of what's possible, but XRegExp has more syntax, flags, methods, options, and browser fixes that aren't shown here. You can also augment XRegExp's regular expression syntax with addons (see below) or write your own. See xregexp.com for details.

Addons

You can either load addons individually, or bundle all addons with XRegExp by loading xregexp-all.js from https://unpkg.com/xregexp/xregexp-all.js.

Unicode

If not using xregexp-all.js, first include the Unicode Base script and then one or more of the addons for Unicode blocks, categories, properties, or scripts.

Then you can do this:

// Test the Unicode category L (Letter)
const unicodeWord = XRegExp('^\\pL+$');
unicodeWord.test('Русский'); // -> true
unicodeWord.test('日本語'); // -> true
unicodeWord.test('العربية'); // -> true

// Test some Unicode scripts
XRegExp('^\\p{Hiragana}+$').test('ひらがな'); // -> true
XRegExp('^[\\p{Latin}\\p{Common}]+$').test('Über Café.'); // -> true

By default, \p{…} and \P{…} support the Basic Multilingual Plane (i.e. code points up to U+FFFF). You can opt-in to full 21-bit Unicode support (with code points up to U+10FFFF) on a per-regex basis by using flag A. This is called astral mode. You can automatically add flag A for all new regexes by running XRegExp.install('astral'). When in astral mode, \p{…} and \P{…} always match a full code point rather than a code unit, using surrogate pairs for code points above U+FFFF.

// Using flag A to match astral code points
XRegExp('^\\pS$').test('💩'); // -> false
XRegExp('^\\pS$', 'A').test('💩'); // -> true
XRegExp('(?A)^\\pS$').test('💩'); // -> true
// Using surrogate pair U+D83D U+DCA9 to represent U+1F4A9 (pile of poo)
XRegExp('(?A)^\\pS$').test('\uD83D\uDCA9'); // -> true

// Implicit flag A
XRegExp.install('astral');
XRegExp('^\\pS$').test('💩'); // -> true

Opting in to astral mode disables the use of \p{…} and \P{…} within character classes. In astral mode, use e.g. (\pL|[0-9_])+ instead of [\pL0-9_]+.

XRegExp uses Unicode 13.0.0.

XRegExp.build

Build regular expressions using named subpatterns, for readability and pattern reuse:

const time = XRegExp.build('(?x)^ {{hours}} ({{minutes}}) $', {
    hours: XRegExp.build('{{h12}} : | {{h24}}', {
        h12: /1[0-2]|0?[1-9]/,
        h24: /2[0-3]|[01][0-9]/
    }),
    minutes: /^[0-5][0-9]$/
});

time.test('10:59'); // -> true
XRegExp.exec('10:59', time).minutes; // -> '59'

Named subpatterns can be provided as strings or regex objects. A leading ^ and trailing unescaped $ are stripped from subpatterns if both are present, which allows embedding independently-useful anchored patterns. {{…}} tokens can be quantified as a single unit. Any backreferences in the outer pattern or provided subpatterns are automatically renumbered to work correctly within the larger combined pattern. The syntax ({{name}}) works as shorthand for named capture via (?<name>{{name}}). Named subpatterns cannot be embedded within character classes.

XRegExp.tag (included with XRegExp.build)

Provides tagged template literals that create regexes with XRegExp syntax and flags:

const h12 = /1[0-2]|0?[1-9]/;
const h24 = /2[0-3]|[01][0-9]/;
const hours = XRegExp.tag('x')`${h12} : | ${h24}`;
const minutes = /^[0-5][0-9]$/;
// Note that explicitly naming the 'minutes' group is required for named backreferences
const time = XRegExp.tag('x')`^ ${hours} (?<minutes>${minutes}) $`;
time.test('10:59'); // -> true
XRegExp.exec('10:59', time).minutes; // -> '59'

XRegExp.tag does more than just basic interpolation. For starters, you get all the XRegExp syntax and flags. Even better, since XRegExp.tag uses your pattern as a raw string, you no longer need to escape all your backslashes. And since it relies on XRegExp.build under the hood, you get all of its extras for free. Leading ^ and trailing unescaped $ are stripped from interpolated patterns if both are present (to allow embedding independently useful anchored regexes), interpolating into a character class is an error (to avoid unintended meaning in edge cases), interpolated patterns are treated as atomic units when quantified, interpolated strings have their special characters escaped, and any backreferences within an interpolated regex are rewritten to work within the overall pattern.

XRegExp.matchRecursive

Match recursive constructs using XRegExp pattern strings as left and right delimiters:

const str1 = '(t((e))s)t()(ing)';
XRegExp.matchRecursive(str1, '\\(', '\\)', 'g');
// -> ['t((e))s', '', 'ing']

// Extended information mode with valueNames
const str2 = 'Here is <div> <div>an</div></div> example';
XRegExp.matchRecursive(str2, '<div\\s*>', '</div>', 'gi', {
    valueNames: ['between', 'left', 'match', 'right']
});
/* -> [
{name: 'between', value: 'Here is ',       start: 0,  end: 8},
{name: 'left',    value: '<div>',          start: 8,  end: 13},
{name: 'match',   value: ' <div>an</div>', start: 13, end: 27},
{name: 'right',   value: '</div>',         start: 27, end: 33},
{name: 'between', value: ' example',       start: 33, end: 41}
] */

// Omitting unneeded parts with null valueNames, and using escapeChar
const str3 = '...{1}.\\{{function(x,y){return {y:x}}}';
XRegExp.matchRecursive(str3, '{', '}', 'g', {
    valueNames: ['literal', null, 'value', null],
    escapeChar: '\\'
});
/* -> [
{name: 'literal', value: '...',  start: 0, end: 3},
{name: 'value',   value: '1',    start: 4, end: 5},
{name: 'literal', value: '.\\{', start: 6, end: 9},
{name: 'value',   value: 'function(x,y){return {y:x}}', start: 10, end: 37}
] */

// Sticky mode via flag y
const str4 = '<1><<<2>>><3>4<5>';
XRegExp.matchRecursive(str4, '<', '>', 'gy');
// -> ['1', '<<2>>', '3']

XRegExp.matchRecursive throws an error if it scans past an unbalanced delimiter in the target string.

Installation and usage

In browsers (bundle XRegExp with all of its addons):

<script src="https://unpkg.com/xregexp/xregexp-all.js"></script>

Using npm:

npm install xregexp

In Node.js:

const XRegExp = require('xregexp');

In an AMD loader like RequireJS:

require({paths: {xregexp: 'xregexp-all'}}, ['xregexp'], (XRegExp) => {
    console.log(XRegExp.version);
});

About

All code, including addons, tools, and tests, is released under the terms of the MIT License.

Fork me to show support, fix, and extend.

Learn more at xregexp.com.

Native support detection / RegExp flags

XRegExp internally detects if the JS engine supports any of these RegExp flags:

u (defined in ES6 standard)
y (defined in ES6 standard)
g
i
m

These (and other flags registered by XRegExp addons) can be queried via the XRegExp._registeredFlags() API, e.g. when you want to include this information in a system diagnostics report which accompanies a user or automated bug report.

APIs

XRegExp(pattern, flags) constructor

Creates an extended regular expression object for matching text with a pattern. Differs from a native regular expression in that additional syntax and flags are supported. The returned object is in fact a native RegExp and works with all native methods.

pattern : {String|RegExp} Regex pattern string, or an existing regex object to copy.

flags : {String} (optional) Any combination of flags.

Native flags:

g - global
i - ignore case
m - multiline anchors
u - unicode (ES6)
y - sticky (Firefox 3+, ES6)

Additional XRegExp flags:

n - explicit capture
s - dot matches all (aka singleline)
x - free-spacing and line comments (aka extended)
A - astral (requires the Unicode Base addon)

Flags cannot be provided when constructing one RegExp from another.

Returns {RegExp} Extended regular expression object.

Example

// With named capture and flag x
XRegExp('(?<year>  [0-9]{4} ) -?  # year  \
         (?<month> [0-9]{2} ) -?  # month \
         (?<day>   [0-9]{2} )     # day   ', 'x');

// Providing a regex object copies it. Native regexes are recompiled using native (not XRegExp)
// syntax. Copies maintain extended data, are augmented with `XRegExp.prototype` properties, and
// have fresh `lastIndex` properties (set to zero).
XRegExp(/regex/);

XRegExp.version

The XRegExp version number as a string containing three dot-separated parts. For example, '2.0.0-beta-3'.

XRegExp: Public methods

XRegExp.addToken(regex, handler, options)

Extends XRegExp syntax and allows custom flags. This is used internally and can be used to create XRegExp addons. If more than one token can match the same string, the last added wins.

regex : {RegExp} Regex object that matches the new token.

handler : {Function} Function that returns a new pattern string (using native regex syntax) to replace the matched token within all future XRegExp regexes. Has access to persistent properties of the regex being built, through this. Invoked with three arguments:

The match array, with named backreference properties.
The regex scope where the match was found: 'default' or 'class'.
The flags used by the regex, including any flags in a leading mode modifier.

The handler function becomes part of the XRegExp construction process, so be careful not to construct XRegExps within the function or you will trigger infinite recursion.

options : {Object} (optional) Options object with optional properties:

scope {String} Scope where the token applies: 'default 'class or 'all'.
flag {String} Single-character flag that triggers the token. This also registers the flag, which prevents XRegExp from throwing an 'unknown flag' error when the flag is used.
optionalFlags {String} Any custom flags checked for within the token handler that are not required to trigger the token. This registers the flags, to prevent XRegExp from throwing an 'unknown flag' error when any of the flags are used.
reparse {Boolean} Whether the handler function's output should not be treated as final, and instead be reparseable by other tokens (including the current token). Allows token chaining or deferring.
leadChar {String} Single character that occurs at the beginning of any successful match of the token (not always applicable). This doesn't change the behavior of the token unless you provide an erroneous value. However, providing it can increase the token's performance since the token can be skipped at any positions where this character doesn't appear.

Examples

// Basic usage: Add \a for the ALERT control code
XRegExp.addToken(
  /\\a/,
  function() {return '\\x07';},
  {scope: 'all'}
);
XRegExp('\\a[\\a-\\n]+').test('\x07\n\x07'); // -> true

// Add the U (ungreedy) flag from PCRE and RE2, which reverses greedy and lazy quantifiers.
// Since `scope` is not specified, it uses 'default' (i.e., transformations apply outside of
// character classes only)
XRegExp.addToken(
  /([?*+]|{\d+(?:,\d*)?})(\??)/,
  function(match) {return match[1] + (match[2] ? '' : '?');},
  {flag: 'U'}
);
XRegExp('a+', 'U').exec('aaa')[0]; // -> 'a'
XRegExp('a+?', 'U').exec('aaa')[0]; // -> 'aaa'

XRegExp.cache(pattern, flags)

Caches and returns the result of calling XRegExp(pattern, flags). On any subsequent call with the same pattern and flag combination, the cached copy of the regex is returned.

pattern : {String} Regex pattern string.

flags : {String} (optional) Any combination of XRegExp flags.

Returns {RegExp} Cached XRegExp object.

Example

while (match = XRegExp.cache('.', 'gs').exec(str)) {
  // The regex is compiled once only
}

XRegExp.cache.flush(cacheName)

XRegExp.escape(str)

Escapes any regular expression metacharacters, for use when matching literal strings. The result can safely be used at any point within a regex that uses any flags.

str : {String} String to escape.

Returns {String} String with regex metacharacters escaped.

Example

XRegExp.escape('Escaped? <.>');
// -> 'Escaped\?\ <\.>'

XRegExp.exec(str, regex, pos, sticky)

Executes a regex search in a specified string. Returns a match array or null. If the provided regex uses named capture, named backreference properties are included on the match array. Optional pos and sticky arguments specify the search start position, and whether the match must start at the specified position only. The lastIndex property of the provided regex is not used, but is updated for compatibility. Also fixes browser bugs compared to the native RegExp.prototype.exec and can be used reliably cross-browser.

str : {String} String to search.

regex : {RegExp} Regex to search with.

pos : {Number} [default: pos=0] Zero-based index at which to start the search.

sticky : {Boolean|String} [default: sticky=false] Whether the match must start at the specified position only. The string 'sticky' is accepted as an alternative to true.

Returns the match array with named backreference properties, or null.

// Basic use, with named backreference
var match = XRegExp.exec('U+2620', XRegExp('U\\+(?<hex>[0-9A-F]{4})'));
match.hex; // -> '2620'

// With pos and sticky, in a loop
var pos = 2, result = [], match;
while (match = XRegExp.exec('<1><2><3><4>5<6>', /<(\d)>/, pos, 'sticky')) {
  result.push(match[1]);
  pos = match.index + match[0].length;
}
// result -> ['2', '3', '4']

XRegExp.forEach(str, regex, callback)

Executes a provided function once per regex match. Searches always start at the beginning of the string and continue until the end, regardless of the state of the regex's global property and initial lastIndex.

str : {String} String to search.

regex : {RegExp} Regex to search with.

callback : {Function} Function to execute for each match. Invoked with four arguments:

The match array, with named backreference properties.
The zero-based match index.
The string being traversed.
The regex object being used to traverse the string.

Example

// Extracts every other digit from a string
var evens = [];
XRegExp.forEach('1a2345', /\d/, function(match, i) {
  if (i % 2) evens.push(+match[0]);
});
// evens -> [2, 4]

XRegExp.globalize(regex)

Copies a regex object and adds flag g. The copy maintains extended data, is augmented with XRegExp.prototype properties, and has a fresh lastIndex property (set to zero). Native regexes are not recompiled using XRegExp syntax.

regex : {RegExp} Regex to globalize.

Returns a copy of the provided regex with flag g added.

var globalCopy = XRegExp.globalize(/regex/);
globalCopy.global; // -> true

XRegExp.install(options)

Installs optional features according to the specified options. Can be undone using XRegExp.uninstall.

options : {Object|String} Feature options object or feature string.

feature: astral

Enables or disables implicit astral mode opt-in. When enabled, flag A is automatically added to all new regexes created by XRegExp. This causes an error to be thrown when creating regexes if the Unicode Base addon is not available, since flag A is registered by that addon.

astral : {Boolean} true to enable; false to disable.

feature: natives

Native methods to use and restore ('native' is an ES3 reserved keyword).

These native methods are overridden:

exec: RegExp.prototype.exec
test: RegExp.prototype.test
match: String.prototype.match
replace: String.prototype.replace
split: String.prototype.split

Examples

// With an options object
XRegExp.install({
  // Enables support for astral code points in Unicode addons (implicitly sets flag A)
  astral: true,

  // DEPRECATED: Overrides native regex methods with fixed/extended versions
  natives: true
});

// With an options string
XRegExp.install('astral natives');

XRegExp.isInstalled(feature)

Checks whether an individual optional feature is installed.

feature : {String} Name of the feature to check. One of:

astral
natives

Return a {Boolean} value indicating whether the feature is installed.

XRegExp.isInstalled('astral');

XRegExp.isRegExp(value)

Returns true if an object is a regex; false if it isn't. This works correctly for regexes created in another frame, when instanceof and constructor checks would fail.

value : {any type allowed} The object to check.

Returns a {Boolean} value indicating whether the object is a RegExp object.

XRegExp.isRegExp('string'); // -> false
XRegExp.isRegExp(/regex/i); // -> true
XRegExp.isRegExp(RegExp('^', 'm')); // -> true
XRegExp.isRegExp(XRegExp('(?s).')); // -> true

XRegExp.match(str, regex, scope)

Returns the first matched string, or in global mode, an array containing all matched strings. This is essentially a more convenient re-implementation of String.prototype.match that gives the result types you actually want (string instead of exec-style array in match-first mode, and an empty array instead of null when no matches are found in match-all mode). It also lets you override flag g and ignore lastIndex, and fixes browser bugs.

str : {String} String to search.

regex : {RegExp} Regex to search with.

scope : {String} [default: scope='one'] Use 'one' to return the first match as a string. Use 'all' to return an array of all matched strings. If not explicitly specified and regex uses flag g, scope is 'all'.

Returns a {String} in match-first mode: First match as a string, or null.

Returns an {Array} in match-all mode: Array of all matched strings, or an empty array.

// Match first
XRegExp.match('abc', /\w/); // -> 'a'
XRegExp.match('abc', /\w/g, 'one'); // -> 'a'
XRegExp.match('abc', /x/g, 'one'); // -> null

// Match all
XRegExp.match('abc', /\w/g); // -> ['a  'b  'c']
XRegExp.match('abc', /\w/, 'all'); // -> ['a  'b  'c']
XRegExp.match('abc', /x/, 'all'); // -> []

XRegExp.matchChain(str, chain)

Retrieves the matches from searching a string using a chain of regexes that successively search within previous matches. The provided chain array can contain regexes and or objects with regex and backref properties. When a backreference is specified, the named or numbered backreference is passed forward to the next regex or returned.

str : {String} String to search.

chain : {Array} Regexes that each search for matches within preceding results.

Returns an {Array} of matches by the last regex in the chain, or an empty array.

// Basic usage; matches numbers within <b> tags
XRegExp.matchChain('1 <b>2</b> 3 <b>4 a 56</b>', [
  XRegExp('(?is)<b>.*?</b>'),
  /\d+/
]);
// -> ['2', '4', '56']

// Passing forward and returning specific backreferences
html = '<a href="http://xregexp.com/api/">XRegExp</a>\
        <a href="http://www.google.com/">Google</a>';
XRegExp.matchChain(html, [
  {regex: /<a href="([^"]+)">/i, backref: 1},
  {regex: XRegExp('(?i)^https?://(?<domain>[^/?#]+)'), backref: 'domain'}
]);
// -> ['xregexp.com', 'www.google.com']

XRegExp.replace(str, search, replacement, scope)

Returns a new string with one or all matches of a pattern replaced. The pattern can be a string or regex, and the replacement can be a string or a function to be called for each match. To perform a global search and replace, use the optional scope argument or include flag g if using a regex. Replacement strings can use ${n} for named and numbered backreferences. Replacement functions can use named backreferences via arguments[0].name. Also fixes browser bugs compared to the native String.prototype.replace and can be used reliably cross-browser.

str : {String} String to search.

search : {RegExp|String} Search pattern to be replaced.

replacement : {String|Function} Replacement string or a function invoked to create it.

Replacement strings can include special replacement syntax:

$$ - Inserts a literal $ character.
$&, $0 - Inserts the matched substring.
`$`` - Inserts the string that precedes the matched substring (left context).
$' - Inserts the string that follows the matched substring (right context).
$n, $nn - Where n/nn are digits referencing an existent capturing group, inserts backreference n/nn.
${n} - Where n is a name or any number of digits that reference an existent capturing group, inserts backreference n.

Replacement functions are invoked with three or more arguments:

The matched substring (corresponds to $& above). Named backreferences are accessible as properties of this first argument.
0..n arguments, one for each backreference (corresponding to $1, $2, etc. above).
The zero-based index of the match within the total search string.
The total string being searched.

scope : {String} [default: scope='one'] Use 'one' to replace the first match only, or 'all'. If not explicitly specified and using a regex with flag g, scope is 'all'.

Returns a new string with one or all matches replaced.

// Regex search, using named backreferences in replacement string
var name = XRegExp('(?<first>\\w+) (?<last>\\w+)');
XRegExp.replace('John Smith', name, '${last}, ${first}');
// -> 'Smith, John'

// Regex search, using named backreferences in replacement function
XRegExp.replace('John Smith', name, function(match) {
  return match.last + ', ' + match.first;
});
// -> 'Smith, John'
 
// String search, with replace-all
XRegExp.replace('RegExp builds RegExps', 'RegExp', 'XRegExp', 'all');
// -> 'XRegExp builds XRegExps'

XRegExp.replaceEach(str, replacements)

Performs batch processing of string replacements. Used like XRegExp.replace, but accepts an array of replacement details. Later replacements operate on the output of earlier replacements. Replacement details are accepted as an array with a regex or string to search for, the replacement string or function, and an optional scope of 'one' or 'all'. Uses the XRegExp replacement text syntax, which supports named backreference properties via ${name}.

str : {String} String to search.

replacements : {Array} Array of replacement detail arrays.

Return a new string with all replacements.

str = XRegExp.replaceEach(str, [
  [XRegExp('(?<name>a)'), 'z${name}'],
  [/b/gi, 'y'],
  [/c/g, 'x', 'one'], // scope 'one' overrides /g
  [/d/, 'w', 'all'],  // scope 'all' overrides lack of /g
  ['e', 'v', 'all'],  // scope 'all' allows replace-all for strings
  [/f/g, function($0) {
    return $0.toUpperCase();
  }]
]);

XRegExp.split(str, separator, limit)

Splits a string into an array of strings using a regex or string separator. Matches of the separator are not included in the result array. However, if separator is a regex that contains capturing groups, backreferences are spliced into the result each time separator is matched. Fixes browser bugs compared to the native String.prototype.split and can be used reliably cross-browser.

str : {String} String to split.

separator : {RegExp|String} Regex or string to use for separating the string.

limit : {Number} (optional) Maximum number of items to include in the result array.

Returns an array of substrings.

// Basic use
XRegExp.split('a b c', ' ');
// -> ['a', 'b', 'c']
 
// With limit
XRegExp.split('a b c', ' ', 2);
// -> ['a', 'b']
 
// Backreferences in result array
XRegExp.split('..word1..', /([a-z]+)(\d+)/i);
// -> ['..', 'word', '1', '..']

XRegExp.test(str, regex, pos, sticky)

Executes a regex search in a specified string. Returns true or false. Optional pos and sticky arguments specify the search start position, and whether the match must start at the specified position only. The lastIndex property of the provided regex is not used, but is updated for compatibility. Also fixes browser bugs compared to the native RegExp.prototype.test and can be used reliably cross-browser.

str : {String} String to search.

regex : {RegExp} Regex to search with.

pos : {Number} [default: pos=0] Zero-based index at which to start the search.

sticky : {Boolean|String} [default: sticky=false] Whether the match must start at the specified position only. The string 'sticky' is accepted as an alternative to true.

Returns a {Boolean} value indicating whether the regex matched the provided value.

// Basic use
XRegExp.test('abc', /c/); // -> true
 
// With pos and sticky
XRegExp.test('abc', /c/, 0, 'sticky'); // -> false
XRegExp.test('abc', /c/, 2, 'sticky'); // -> true

XRegExp.uninstall(options)

Uninstalls optional features according to the specified options. All optional features start out uninstalled, so this is used to undo the actions of XRegExp.install.

options : {Object|String} Feature options object or features string. These features are supported:

astral
natives

// With an options object
XRegExp.uninstall({
  // Disables support for astral code points in Unicode addons
  astral: true,
 
  // DEPRECATED: Restores native regex methods
  natives: true
});

// With an options string
XRegExp.uninstall('astral natives');

XRegExp.join(patterns, separator, flags)

Returns an XRegExp object that is the concatenation of the given patterns. Patterns can be provided as regex objects or strings. Metacharacters are escaped in patterns provided as strings. Backreferences in provided regex objects are automatically renumbered to work correctly within the larger combined pattern. Native flags used by provided regexes are ignored in favor of the flags argument.

patterns : {Array} Regexes and strings to combine.

separator : {String|RegExp} Regex or string to use as the joining separator.

flags : {String} (optional) Any combination of XRegExp flags.

Returns the union regexp of the provided regexes and strings.

XRegExp.join(['a+b*c', /(dogs)\1/, /(cats)\1/], 'i');
// -> /a\+b\*c(dogs)\1(cats)\2/i

XRegExp.union(patterns, flags)

Returns an XRegExp object that is the union of the given patterns. Patterns can be provided as regex objects or strings. Metacharacters are escaped in patterns provided as strings. Backreferences in provided regex objects are automatically renumbered to work correctly within the larger combined pattern. Native flags used by provided regexes are ignored in favor of the flags argument.

patterns : {Array} Regexes and strings to combine.

flags : {String} (optional) Any combination of XRegExp flags.

Returns the union regexp of the provided regexes and strings.

XRegExp.union(['a+b*c', /(dogs)\1/, /(cats)\1/], 'i');
// -> /a\+b\*c|(dogs)\1|(cats)\2/i

Fixed/extended native methods

Calling XRegExp.install('natives') uses this to override the native methods.

RegExp.exec(str)

Adds named capture support (with backreferences returned as result.name), and fixes browser bugs in the native RegExp.prototype.exec. Calling XRegExp.install('natives') uses this to override the native method. Use via XRegExp.exec without overriding natives.

str : {String} String to search.

Returns the match array with named backreference properties, or null.

RegExp.test(str)

Fixes browser bugs in the native RegExp.prototype.test. Calling XRegExp.install('natives') uses this to override the native method.

str : {String} String to search.

Returns a {Boolean} value indicating whether the regex matched the provided value.

String.match(regex)

Adds named capture support (with backreferences returned as result.name), and fixes browser bugs in the native String.prototype.match. Calling XRegExp.install('natives') uses this to override the native method.

regex : {RegExp|*} Regex to search with. If not a regex object, it is passed to the RegExp constructor.

Returns an array of match strings or null, if regex uses flag g.

Returns the result of calling regex.exec(this), if regex was without flag g.

String.replace(search, replacement)

Adds support for ${n} tokens for named and numbered backreferences in replacement text, and provides named backreferences to replacement functions as arguments[0].name. Also fixes browser bugs in replacement text syntax when performing a replacement using a nonregex search value, and the value of a replacement regex's lastIndex property during replacement iterations and upon completion. Calling XRegExp.install('natives') uses this to override the native method. Note that this doesn't support SpiderMonkey's proprietary third (flags) argument. Use via XRegExp.replace without overriding natives.

search : {RegExp|String} Search pattern to be replaced.

replacement : {String|Function} Replacement string or a function invoked to create it.

Returns a new string with one or all matches replaced.

String.split(separator, limit)

Fixes browser bugs in the native String.prototype.split. Calling XRegExp.install('natives') uses this to override the native method. Use via XRegExp.split without overriding natives.

separator : {RegExp|String} Regex or string to use for separating the string.

limit : {Number} (optional) Maximum number of items to include in the result array.

Returns an array of substrings.

Enhanced regex support features

Letter Escapes are errors (unless...)

Letter escapes that natively match literal characters: \a, \A, etc. These should be SyntaxErrors but are allowed in web reality. XRegExp makes them errors for cross-browser consistency and to reserve their syntax, but lets them be superseded by addons.

XRegExp.addToken(
    /\\([ABCE-RTUVXYZaeg-mopqyz]|c(?![A-Za-z])|u(?![\dA-Fa-f]{4}|{[\dA-Fa-f]+})|x(?![\dA-Fa-f]{2}))/, ...

Unicode code point escapes (with curly braces)

Unicode code point escape with curly braces: \u{N..}. N.. is any one or more digit hexadecimal number from 0-10FFFF, and can include leading zeros. Requires the native ES6 u flag to support code points greater than U+FFFF. Avoids converting code points above U+FFFF to surrogate pairs (which could be done without flag u), since that could lead to broken behavior if you follow a \u{N..} token that references a code point above U+FFFF with a quantifier, or if you use the same in a character class.

XRegExp.addToken(
    /\\u{([\dA-Fa-f]+)}/, ...

Empty character class

Empty character class: [] or [^]. This fixes a critical cross-browser syntax inconsistency. Unless this is standardized (per the ES spec), regex syntax can't be accurately parsed because character class endings can't be determined.

XRegExp.addToken(
    /\[(\^?)\]/, ...

Regex comment pattern

Comment pattern: (?# ). Inline comments are an alternative to the line comments allowed in free-spacing mode (flag x).

XRegExp.addToken(
    /\(\?#[^)]*\)/, ...

Free-spacing mode a.k.a. extended mode regexes

Whitespace and line comments, in free-spacing mode (aka extended mode, flag x) only.

XRegExp.addToken(
    /\s+|#[^\n]*\n?/, ...

Dotall mode a.k.a. singleline mode (`s` flag)

Dot, in dotall mode (aka singleline mode, flag s) only.

XRegExp.addToken(
    /\./,
    function() {
        return '[\\s\\S]';
    },
    {
        flag: 's',
        leadChar: '.'
    }
);

Named backreference

Named backreference: \k<name>. Backreference names can use the characters A-Z, a-z, 0-9, _, and $ only. Also allows numbered backreferences as \k<n>.

XRegExp.addToken(
    /\\k<([\w$]+)>/, ...

Numbered backreference

Numbered backreference or octal, plus any following digits: \0, \11, etc. Octals except \0 not followed by 0-9 and backreferences to unopened capture groups throw an error. Other matches are returned unaltered. IE < 9 doesn't support backreferences above \99 in regex syntax.

XRegExp.addToken(
    /\\(\d+)/, ...

Named capture group

Named capturing group; match the opening delimiter only: (?<name>. Capture names can use the characters A-Z, a-z, 0-9, _, and $ only. Names can't be integers. Supports Python-style (?P<name> as an alternate syntax to avoid issues in some older versions of Opera which natively supported the Python-style syntax. Otherwise, XRegExp might treat numbered backreferences to Python-style named capture as octals.

XRegExp.addToken(
    /\(\?P?<([\w$]+)>/, ...

Capture group & explicit capture mode (`n` flag)

Capturing group; match the opening parenthesis only. Required for support of named capturing groups. Also adds explicit capture mode (flag n).

XRegExp.addToken(
    /\((?!\?)/,
    {
        optionalFlags: 'n',
        leadChar: '('
    }

XRegExp.build(pattern, subs, flags)

Builds regexes using named subpatterns, for readability and pattern reuse. Backreferences in the outer pattern and provided subpatterns are automatically renumbered to work correctly. Native flags used by provided subpatterns are ignored in favor of the flags argument.

pattern : {String} XRegExp pattern using {{name}} for embedded subpatterns. Allows ({{name}}) as shorthand for (?<name>{{name}}). Patterns cannot be embedded within character classes.

subs
: {Object} Lookup object for named subpatterns. Values can be strings or regexes. A leading ^ and trailing unescaped $ are stripped from subpatterns, if both are present.

flags : {String} (optional) Any combination of XRegExp flags.

Returns a regexp with interpolated subpatterns.

var time = XRegExp.build('(?x)^ {{hours}} ({{minutes}}) $', {
  hours: XRegExp.build('{{h12}} : | {{h24}}', {
    h12: /1[0-2]|0?[1-9]/,
    h24: /2[0-3]|[01][0-9]/
  }, 'x'),
  minutes: /^[0-5][0-9]$/
});
time.test('10:59'); // -> true
XRegExp.exec('10:59', time).minutes; // -> '59'

XRegExp.matchRecursive(str, left, right, flags, options)

Returns an array of match strings between outermost left and right delimiters, or an array of objects with detailed match parts and position data. An error is thrown if delimiters are unbalanced within the data.

str : {String} String to search.

left : {String} Left delimiter as an XRegExp pattern.

right : {String} Right delimiter as an XRegExp pattern.

flags : {String} (optional) Any native or XRegExp flags, used for the left and right delimiters.

options : {Object} (optional) Lets you specify valueNames and escapeChar options.

Returns an array of matches, or an empty array.

// Basic usage
var str = '(t((e))s)t()(ing)';
XRegExp.matchRecursive(str, '\\(', '\\)', 'g');
// -> ['t((e))s', ' ', 'ing']
 
// Extended information mode with valueNames
str = 'Here is <div> <div>an</div></div> example';
XRegExp.matchRecursive(str, '<div\\s*>', '</div>', 'gi', {
  valueNames: ['between', 'left', 'match', 'right']
});
// -> [
// {name: 'between', value: 'Here is ',       start: 0,  end: 8},
// {name: 'left',    value: '<div>',          start: 8,  end: 13},
// {name: 'match',   value: ' <div>an</div>', start: 13, end: 27},
// {name: 'right',   value: '</div>',         start: 27, end: 33},
// {name: 'between', value: ' example',       start: 33, end: 41}
// ]
 
// Omitting unneeded parts with null valueNames, and using escapeChar
str = '...{1}.\\{{function(x,y){return {y:x}}}';
XRegExp.matchRecursive(str, '{', '}', 'g', {
  valueNames: ['literal', null, 'value', null],
  escapeChar: '\\'
});
// -> [
// {name: 'literal', value: '...',  start: 0, end: 3},
// {name: 'value',   value: '1',    start: 4, end: 5},
// {name: 'literal', value: '.\\{', start: 6, end: 9},
// {name: 'value',   value: 'function(x,y){return {y:x};}', start: 10, end: 37}
// ]
 
// Sticky mode via flag y
str = '<1><<<2>>><3>4<5>';
XRegExp.matchRecursive(str, '<', '>', 'gy');
// -> ['1', '<<2>>', '3']

Unicode matching (`\p{..}`, `\P{..}`, `\p{^..}`, `\pC`) & astral mode (`A` flag)

XRegExp adds base support for Unicode matching:

Adds syntax \p{..} for matching Unicode tokens. Tokens can be inverted using \P{..} or \p{^..}. Token names ignore case, spaces, hyphens, and underscores. You can omit the braces for token names that are a single letter (e.g. \pL or PL).
Adds flag A (astral), which enables 21-bit Unicode support.
Adds the XRegExp.addUnicodeData method used by other addons to provide character data.

Unicode Base relies on externally provided Unicode character data. Official addons are available to provide data for Unicode categories, scripts, blocks, and properties via XRegExp.addToken() API.

XRegExp.addUnicodeData(data)

Adds to the list of Unicode tokens that XRegExp regexes can match via \p or \P.

data {Array} Objects with named character ranges. Each object may have properties name, alias, isBmpLast, inverseOf, bmp, and astral. All but name are optional, although one of bmp or astral is required (unless inverseOf is set). If astral is absent, the bmp data is used for BMP and astral modes. If bmp is absent, the name errors in BMP mode but works in astral mode. If both bmp and astral are provided, the bmp data only is used in BMP mode, and the combination of bmp and astral data is used in astral mode. isBmpLast is needed when a token matches orphan high surrogates and uses surrogate pairs to match astral code points. The bmp and astral data should be a combination of literal characters and \xHH or \uHHHH escape sequences, with hyphens to create ranges. Any regex metacharacters in the data should be escaped, apart from range-creating hyphens. The astral data can additionally use character classes and alternation, and should use surrogate pairs to represent astral code points. inverseOf can be used to avoid duplicating character data if a Unicode token is defined as the exact inverse of another token.

// Basic use
XRegExp.addUnicodeData([{
  name: 'XDigit',
  alias: 'Hexadecimal',
  bmp: '0-9A-Fa-f'
}]);
XRegExp('\\p{XDigit}:\\p{Hexadecimal}+').test('0:3D'); // -> true

Private / Unofficial / Unsupported APIs

XRegExp._registeredFlags()

Returns a reference to the internal registered flags object, where each flag is a hash key:

var flags = XRegExp._registeredFlags();
assert(flags['u'], 'expected native Unicode support');

function setNatives(on)

Enables or disables native method overrides.

on : {Boolean} true to enable; false to disable.

Used internally by the XRegExp.install() and XRegExp.uninstall() APIs; setNatives() is itself not accessibly externally (private function).

XRegExp._hasNativeFlag(flag)

Check if the regex flag is supported natively in your environment.

Returns {Boolean}.

XRegExp._dec(hex)

Converts hexadecimal to decimal.

hex : {String}

Returns {Number}

XRegExp._hex(dec)

Converts decimal to hexadecimal.

dec : {Number|String}

Returns {String}

XRegExp._pad4(str)

Adds leading zeros if shorter than four characters. Used for fixed-length hexadecimal values.

str : {String}

Returns {String}

XRegExp._getUnicodeProperty(name)

Return a reference to the internal Unicode definition structure for the given Unicode Property if the given name is a legal Unicode Property for use in XRegExp \p or \P regex constructs.

name : {String} Name by which the Unicode Property may be recognized (case-insensitive), e.g. 'N' or 'Number'.

The given name is matched against all registered Unicode Properties and Property Aliases.

Token names are case insensitive, and any spaces, hyphens, and underscores are ignored.

Returns {Object} reference to definition structure when the name matches a Unicode Property; false when the name does not match any Unicode Property or Property Alias.

Notes

For more info on Unicode Properties, see also http://unicode.org/reports/tr18/#Categories.

This method is not part of the officially documented and published API and is meant 'for advanced use only' where userland code wishes to re-use the (large) internal Unicode structures set up by XRegExp as a single point of Unicode 'knowledge' in the application.

See some example usage of this functionality, used as a boolean check if the given name is legal and to obtain internal structural data:

function prepareMacros(...) in https://github.com/GerHobbelt/jison-lex/blob/master/regexp-lexer.js#L885
function generateRegexesInitTableCode(...) in https://github.com/GerHobbelt/jison-lex/blob/master/regexp-lexer.js#L1999

Note that the second function in the example (function generateRegexesInitTableCode(...)) uses a approach without using this API to obtain a Unicode range spanning regex for use in environments which do not support XRegExp by simply expanding the XRegExp instance to a String through the map() mapping action and subsequent join().

Unicode Blocks, Categories, Properties and Scripts

XRegExp adds support for all Unicode blocks. Block names use the prefix 'In'. E.g. \p{InBasicLatin}. Token names are case insensitive, and any spaces, hyphens, and underscores are ignored.

Currently XRegExp supports the Unicode 8.0.0 block names listed below:

InAegean_Numbers
InAhom
InAlchemical_Symbols
InAlphabetic_Presentation_Forms
InAnatolian_Hieroglyphs
InAncient_Greek_Musical_Notation
InAncient_Greek_Numbers
InAncient_Symbols
InArabic
InArabic_Extended_A
InArabic_Mathematical_Alphabetic_Symbols
InArabic_Presentation_Forms_A
InArabic_Presentation_Forms_B
InArabic_Supplement
InArmenian
InArrows
InAvestan
InBalinese
InBamum
InBamum_Supplement
InBasic_Latin
InBassa_Vah
InBatak
InBengali
InBlock_Elements
InBopomofo
InBopomofo_Extended
InBox_Drawing
InBrahmi
InBraille_Patterns
InBuginese
InBuhid
InByzantine_Musical_Symbols
InCarian
InCaucasian_Albanian
InChakma
InCham
InCherokee
InCherokee_Supplement
InCJK_Compatibility
InCJK_Compatibility_Forms
InCJK_Compatibility_Ideographs
InCJK_Compatibility_Ideographs_Supplement
InCJK_Radicals_Supplement
InCJK_Strokes
InCJK_Symbols_and_Punctuation
InCJK_Unified_Ideographs
InCJK_Unified_Ideographs_Extension_A
InCJK_Unified_Ideographs_Extension_B
InCJK_Unified_Ideographs_Extension_C
InCJK_Unified_Ideographs_Extension_D
InCJK_Unified_Ideographs_Extension_E
InCombining_Diacritical_Marks
InCombining_Diacritical_Marks_Extended
InCombining_Diacritical_Marks_for_Symbols
InCombining_Diacritical_Marks_Supplement
InCombining_Half_Marks
InCommon_Indic_Number_Forms
InControl_Pictures
InCoptic
InCoptic_Epact_Numbers
InCounting_Rod_Numerals
InCuneiform
InCuneiform_Numbers_and_Punctuation
InCurrency_Symbols
InCypriot_Syllabary
InCyrillic
InCyrillic_Extended_A
InCyrillic_Extended_B
InCyrillic_Supplement
InDeseret
InDevanagari
InDevanagari_Extended
InDingbats
InDomino_Tiles
InDuployan
InEarly_Dynastic_Cuneiform
InEgyptian_Hieroglyphs
InElbasan
InEmoticons
InEnclosed_Alphanumeric_Supplement
InEnclosed_Alphanumerics
InEnclosed_CJK_Letters_and_Months
InEnclosed_Ideographic_Supplement
InEthiopic
InEthiopic_Extended
InEthiopic_Extended_A
InEthiopic_Supplement
InGeneral_Punctuation
InGeometric_Shapes
InGeometric_Shapes_Extended
InGeorgian
InGeorgian_Supplement
InGlagolitic
InGothic
InGrantha
InGreek_and_Coptic
InGreek_Extended
InGujarati
InGurmukhi
InHalfwidth_and_Fullwidth_Forms
InHangul_Compatibility_Jamo
InHangul_Jamo
InHangul_Jamo_Extended_A
InHangul_Jamo_Extended_B
InHangul_Syllables
InHanunoo
InHatran
InHebrew
InHigh_Private_Use_Surrogates
InHigh_Surrogates
InHiragana
InIdeographic_Description_Characters
InImperial_Aramaic
InInscriptional_Pahlavi
InInscriptional_Parthian
InIPA_Extensions
InJavanese
InKaithi
InKana_Supplement
InKanbun
InKangxi_Radicals
InKannada
InKatakana
InKatakana_Phonetic_Extensions
InKayah_Li
InKharoshthi
InKhmer
InKhmer_Symbols
InKhojki
InKhudawadi
InLao
InLatin_1_Supplement
InLatin_Extended_A
InLatin_Extended_Additional
InLatin_Extended_B
InLatin_Extended_C
InLatin_Extended_D
InLatin_Extended_E
InLepcha
InLetterlike_Symbols
InLimbu
InLinear_A
InLinear_B_Ideograms
InLinear_B_Syllabary
InLisu
InLow_Surrogates
InLycian
InLydian
InMahajani
InMahjong_Tiles
InMalayalam
InMandaic
InManichaean
InMathematical_Alphanumeric_Symbols
InMathematical_Operators
InMeetei_Mayek
InMeetei_Mayek_Extensions
InMende_Kikakui
InMeroitic_Cursive
InMeroitic_Hieroglyphs
InMiao
InMiscellaneous_Mathematical_Symbols_A
InMiscellaneous_Mathematical_Symbols_B
InMiscellaneous_Symbols
InMiscellaneous_Symbols_and_Arrows
InMiscellaneous_Symbols_and_Pictographs
InMiscellaneous_Technical
InModi
InModifier_Tone_Letters
InMongolian
InMro
InMultani
InMusical_Symbols
InMyanmar
InMyanmar_Extended_A
InMyanmar_Extended_B
InNabataean
InNew_Tai_Lue
InNKo
InNumber_Forms
InOgham
InOl_Chiki
InOld_Hungarian
InOld_Italic
InOld_North_Arabian
InOld_Permic
InOld_Persian
InOld_South_Arabian
InOld_Turkic
InOptical_Character_Recognition
InOriya
InOrnamental_Dingbats
InOsmanya
InPahawh_Hmong
InPalmyrene
InPau_Cin_Hau
InPhags_pa
InPhaistos_Disc
InPhoenician
InPhonetic_Extensions
InPhonetic_Extensions_Supplement
InPlaying_Cards
InPrivate_Use_Area
InPsalter_Pahlavi
InRejang
InRumi_Numeral_Symbols
InRunic
InSamaritan
InSaurashtra
InSharada
InShavian
InShorthand_Format_Controls
InSiddham
InSinhala
InSinhala_Archaic_Numbers
InSmall_Form_Variants
InSora_Sompeng
InSpacing_Modifier_Letters
InSpecials
InSundanese
InSundanese_Supplement
InSuperscripts_and_Subscripts
InSupplemental_Arrows_A
InSupplemental_Arrows_B
InSupplemental_Arrows_C
InSupplemental_Mathematical_Operators
InSupplemental_Punctuation
InSupplemental_Symbols_and_Pictographs
InSupplementary_Private_Use_Area_A
InSupplementary_Private_Use_Area_B
InSutton_SignWriting
InSyloti_Nagri
InSyriac
InTagalog
InTagbanwa
InTags
InTai_Le
InTai_Tham
InTai_Viet
InTai_Xuan_Jing_Symbols
InTakri
InTamil
InTelugu
InThaana
InThai
InTibetan
InTifinagh
InTirhuta
InTransport_and_Map_Symbols
InUgaritic
InUnified_Canadian_Aboriginal_Syllabics
InUnified_Canadian_Aboriginal_Syllabics_Extended
InVai
InVariation_Selectors
InVariation_Selectors_Supplement
InVedic_Extensions
InVertical_Forms
InWarang_Citi
InYi_Radicals
InYi_Syllables
InYijing_Hexagram_Symbols

XRegExp adds support for Unicode's general categories. E.g., \p{Lu} or \p{Uppercase Letter}. See category descriptions in UAX #44 http://unicode.org/reports/tr44/#GC_Values_Table. Token names are case insensitive, and any spaces, hyphens, and underscores are ignored.

Currently XRegExp supports the Unicode 8.0.0 category names listed below:

Close_Punctuation
Connector_Punctuation
Control
Currency_Symbol
Dash_Punctuation
Decimal_Number
Enclosing_Mark
Final_Punctuation
Format
Initial_Punctuation
Letter
Letter_Number
Line_Separator
Lowercase_Letter
Mark
Math_Symbol
Modifier_Letter
Modifier_Symbol
Nonspacing_Mark
Number
Open_Punctuation
Other
Other_Letter
Other_Number
Other_Punctuation
Other_Symbol
Paragraph_Separator
Private_Use
Punctuation
Separator
Space_Separator
Spacing_Mark
Surrogate
Symbol
Titlecase_Letter
Unassigned
Uppercase_Letter
C
Cc
Cf
Cn
Co
Cs
L
Ll
Lm
Lo
Lt
Lu
M
Mc
Me
Mn
N
Nd
Nl
No
P
Pc
Pd
Pe
Pf
Pi
Po
Ps
S
Sc
Sk
Sm
So
Z
Zl
Zp
Zs

XRegExp adds properties to meet the UTS #18 Level 1 RL1.2 requirements for Unicode regex support. See http://unicode.org/reports/tr18/#RL1.2. Following are definitions of these properties from UAX #44 http://unicode.org/reports/tr44/:

Alphabetic

Characters with the Alphabetic property. Generated from: Lowercase + Uppercase + Lt + Lm + Lo + Nl + Other_Alphabetic.
Default_Ignorable_Code_Point

For programmatic determination of default ignorable code points. New characters that should be ignored in rendering (unless explicitly supported) will be assigned in these ranges, permitting programs to correctly handle the default rendering of such characters when not otherwise supported.
Lowercase

Characters with the Lowercase property. Generated from: Ll + Other_Lowercase.
Noncharacter_Code_Point

Code points permanently reserved for internal use.
Uppercase

Characters with the Uppercase property. Generated from: Lu + Other_Uppercase.
White_Space

Spaces, separator characters and other control characters which should be treated by programming languages as "white space" for the purpose of parsing elements.

The properties ASCII, Any, and Assigned are also included but are not defined in UAX #44. UTS #18 RL1.2 additionally requires support for Unicode scripts and general categories. These are included in XRegExp's Unicode Categories and Unicode Scripts addons.

Token names are case insensitive, and any spaces, hyphens, and underscores are ignored.

Currently XRegExp supports the Unicode 8.0.0 property names listed below:

Alphabetic
Any
ASCII
Default_Ignorable_Code_Point
Lowercase
Noncharacter_Code_Point
Uppercase
White_Space

Next to these, this property name is available as well:

Assigned

This is defined as the inverse of Unicode category Cn (Unassigned)

XRegExp adds support for all Unicode scripts. E.g., \p{Latin}. Token names are case insensitive, and any spaces, hyphens, and underscores are ignored.

Currently XRegExp supports the Unicode 8.0.0 script names listed below:

Ahom
Anatolian_Hieroglyphs
Arabic
Armenian
Avestan
Balinese
Bamum
Bassa_Vah
Batak
Bengali
Bopomofo
Brahmi
Braille
Buginese
Buhid
Canadian_Aboriginal
Carian
Caucasian_Albanian
Chakma
Cham
Cherokee
Common
Coptic
Cuneiform
Cypriot
Cyrillic
Deseret
Devanagari
Duployan
Egyptian_Hieroglyphs
Elbasan
Ethiopic
Georgian
Glagolitic
Gothic
Grantha
Greek
Gujarati
Gurmukhi
Han
Hangul
Hanunoo
Hatran
Hebrew
Hiragana
Imperial_Aramaic
Inherited
Inscriptional_Pahlavi
Inscriptional_Parthian
Javanese
Kaithi
Kannada
Katakana
Kayah_Li
Kharoshthi
Khmer
Khojki
Khudawadi
Lao
Latin
Lepcha
Limbu
Linear_A
Linear_B
Lisu
Lycian
Lydian
Mahajani
Malayalam
Mandaic
Manichaean
Meetei_Mayek
Mende_Kikakui
Meroitic_Cursive
Meroitic_Hieroglyphs
Miao
Modi
Mongolian
Mro
Multani
Myanmar
Nabataean
New_Tai_Lue
Nko
Ogham
Ol_Chiki
Old_Hungarian
Old_Italic
Old_North_Arabian
Old_Permic
Old_Persian
Old_South_Arabian
Old_Turkic
Oriya
Osmanya
Pahawh_Hmong
Palmyrene
Pau_Cin_Hau
Phags_Pa
Phoenician
Psalter_Pahlavi
Rejang
Runic
Samaritan
Saurashtra
Sharada
Shavian
Siddham
SignWriting
Sinhala
Sora_Sompeng
Sundanese
Syloti_Nagri
Syriac
Tagalog
Tagbanwa
Tai_Le
Tai_Tham
Tai_Viet
Takri
Tamil
Telugu
Thaana
Thai
Tibetan
Tifinagh
Tirhuta
Ugaritic
Vai
Warang_Citi
Yi

Additional token names may be defined via the XRegExp.addUnicodeData(unicodeData) API.

Info for XRegExp Developers

To regenerate the xregexp-all.js source file you can simply run the command

npm run build

in the base directory of the repository.

Credits

XRegExp project collaborators are:

Thanks to all contributors and others who have submitted code, provided feedback, reported bugs, and inspired new features.

XRegExp is released under the MIT License. Learn more at xregexp.com.

@gerhobbelt/xregexp

XRegExp 4.4.0-32

Performance

Usage examples

Addons

Unicode

XRegExp.build

XRegExp.tag (included with XRegExp.build)

XRegExp.matchRecursive

Installation and usage

About

Native support detection / RegExp flags

APIs

XRegExp(pattern, flags) constructor

Example

XRegExp.version

XRegExp: Public methods

XRegExp.addToken(regex, handler, options)

Examples

XRegExp.cache(pattern, flags)

Example

XRegExp.cache.flush(cacheName)

XRegExp.escape(str)

Example

XRegExp.exec(str, regex, pos, sticky)

XRegExp.forEach(str, regex, callback)

Example

XRegExp.globalize(regex)

XRegExp.install(options)

feature: astral

feature: natives

Examples

XRegExp.isInstalled(feature)

XRegExp.isRegExp(value)

XRegExp.match(str, regex, scope)

XRegExp.matchChain(str, chain)

XRegExp.replace(str, search, replacement, scope)

XRegExp.replaceEach(str, replacements)

XRegExp.split(str, separator, limit)

XRegExp.test(str, regex, pos, sticky)

XRegExp.uninstall(options)

XRegExp.join(patterns, separator, flags)

XRegExp.union(patterns, flags)

Fixed/extended native methods

RegExp.exec(str)

RegExp.test(str)

String.match(regex)

String.replace(search, replacement)

String.split(separator, limit)

Enhanced regex support features

Letter Escapes are errors (unless...)

Unicode code point escapes (with curly braces)

Empty character class

Regex comment pattern

Free-spacing mode a.k.a. extended mode regexes

Dotall mode a.k.a. singleline mode (s flag)

Named backreference

Numbered backreference

Named capture group

Capture group & explicit capture mode (n flag)

XRegExp.build(pattern, subs, flags)

XRegExp.matchRecursive(str, left, right, flags, options)

Unicode matching (\p{..}, \P{..}, \p{^..}, \pC) & astral mode (A flag)

XRegExp.addUnicodeData(data)

Private / Unofficial / Unsupported APIs

XRegExp._registeredFlags()

function setNatives(on)

XRegExp._hasNativeFlag(flag)

XRegExp._dec(hex)

XRegExp._hex(dec)

XRegExp._pad4(str)

XRegExp._getUnicodeProperty(name)

Notes

Unicode Blocks, Categories, Properties and Scripts

Info for XRegExp Developers

Credits

Readme

Keywords

Package Sidebar

Install

Dotall mode a.k.a. singleline mode (`s` flag)

Capture group & explicit capture mode (`n` flag)

Unicode matching (`\p{..}`, `\P{..}`, `\p{^..}`, `\pC`) & astral mode (`A` flag)

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