Develop Reference

JavaScript matching unicode letters [duplicate]

i have the following regex that allows only alphabets :
/[a-zA-Z]+/
a = "abcDF"
if (a.match(/[a-zA-Z]+/) == a){
//Match
}else{
//No Match
}
How can I do this using p{L} (universal - any language like german, english etc.. )
What I tried :
a.match(/[p{l}]+/)
a.match(/[\p{l}]+/)
a.match(/p{l}/)
a.match(/\p{l}/)
but all returned null for the letter a = "aB"

Starting with ECMAScript 2018, JavaScript finally supports Unicode property escapes natively.
For older versions, you either need to define all the relevant Unicode ranges yourself. Or you can use Steven Levithan's XRegExp package with Unicode add-ons and utilize its Unicode property shortcuts:
var regex = new XRegExp("^\\p{L}*$")
var a = "abcäöüéèê"
if (regex.test(a)) {
// Match
} else {
// No Match
}

If you are willing to use Babel to build your javascript then there's a babel-plugin I have released which will transform regular expressions like /^\p{L}+$/ or /\p{^White_Space}/ into a regular expression that browsers will understand.
This is the project page: https://github.com/danielberndt/babel-plugin-utf-8-regex

You may use \p{L} with the modern ECMAScript 2018+ compliant JavaScript environments, but you need to remember that the Unicode property classes are only supported when you pass u modifier/flag:
a.match(/\p{L}+/gu)
a.match(/\p{Alphabetic}+/gu)
will match all occurrences of 1 or more Unicode letters in the a string.
NOTE that \p{Alphabetic} (\p{Alpha}) includes all letters matched by \p{L}, plus letter numbers matched by \p{Nl} (e.g. Ⅻ – a character for the roman number 12), plus some other symbols matched with \p{Other_Alphabetic} (\p{OAlpha}).
There are some things to bear in mind though when using u modifier with a regex:
You can use Unicode code point escape sequences such as \u{1F42A} for specifying characters via code points. Normal Unicode escapes such as \u03B1 only have a range of four hexadecimal digits (which equals the basic multilingual plane) (source)
"Characters of 4 bytes are handled correctly: as a single character, not two 2-byte characters" (source)
Escaping requirements to patterns compiled with u flag are more strict: you can't escape any special characters, you can only escape those that can actually behave as special characters. See HTML input pattern not working.

Add Unicode character support to a regexp expression [duplicate]

In JavaScript we can match individual Unicode codepoints or codepoint ranges by using the Unicode escape sequences, e.g.:
"A".match(/\u0041/) // => ["A"]
"B".match(/[\u0041-\u007A]/) // => ["B"]
But how could we create a regular expression to match a proper name which must include any Unicode "letter" using a JavaScript regular expression? Is there a range of letters? A special regex sequence or character class in JavaScript?
Say my website must validate names that could be in latin based languages as well as Hebrew, Cyrillic, Japanese (Katakana, Hiragana, etc.) is this feasible in JavaScript or is the only sane choice to delegate to a backend language with better Unicode support?

Here's a JS plugin that adds Unicode support to RegEx
http://xregexp.com/plugins/

I am using for defining unicode of a symbols this site http://www.fileformat.info.
Unicode Blocks (Basic Latin, .+, Cyrillic, .+, Arabic and other):
http://www.fileformat.info/info/unicode/block/index.htm
Unicode Character Categories (this does not work in JS):
http://www.fileformat.info/info/unicode/category/index.htm
Letters (A-я):
http://www.fileformat.info/info/unicode/char/a.htm
Fonts (which chars are supported in each font):
http://www.fileformat.info/info/unicode/font/index.htm
Index for all above
http://www.fileformat.info/info/unicode/index.htm

How to chech Bosnian-specific characters in RegEx?

I have this Regular Expression pattern, which is quite simple and it validates if the provided string is "alpha" (both uppercase and lowercase):
var pattern = /^[a-zA-Z]+$/gi;
When I trigger pattern.test('Zlatan Omerovic') it returns true, however if I:
pattern.test('Zlatan Omerović');
It returns false and it fails my validation.
In Bosnian language we have these specific characters:
š đ č ć ž
And uppercased:
Š Đ Č Ć Ž
Is it possible to validate these characters (both cases) with JavaScript regular expression?

Sure, you can just add those characters to the list of characters your matching. Also, since you're doing a case insensitive match (the i flag), you don't need the uppercase characters.
var pattern = /^[a-zšđčćž ]+$/gi;
Fiddle here: http://jsfiddle.net/ryanbrill/KB74b/
Here's an alternate pattern, which uses the unicode representation, which might be better (embedding the characters won't work if the file isn't saved with the proper encoding, for instance)
var pattern = /^[a-z\u0161\u0111\u010D\u0107\u017E ]+$/gi;
http://jsfiddle.net/ryanbrill/KB74b/2/

a-zA-Z means exactly that, and in an English-centric way: abcdefghijklmnopqrstuvwxyz. Sadly, with JavaScript's regular expressions, if you want to test other alphabetic characters, you have to specify them specifically. JavaScript doesn't have a locale-sensitive "alpha" definition. To include non-English alphabetic characters, you have to include them on purpose. You can either do that literally (for instance, by including š in the regular expression), or using Unicode escape sequences (such as \u0161). If the additional Bosnian alphabetic characters in question have a contiguous range, you can use the - notation with them as well, but it has to be separate from the a-z, which is defined in English terms.

To include in test result the first (S-based) symbol of your five I did:
var pattern = /^[a-zA-Z\u0160-\u0161]+$/g;
Try to add all the symbols you need this way ;)

Regular expression to allow all alphabet characters plus unicode characters

I need a regular expression to allow all alphabet characters plus Greek/German alphabet in a string but replace those symbols ?,&,^,". with *
I skipped the list with characters to escape to made the question simple.
I really want to see how to construct this and afterwards include alphabet sets using ASCII codes.

if you have a finite and short set of elements to replace you could just use a class e.g.
string.replace(/[?\^&]/g, '*');
and add as many symbols as you want to reject. you could also add ranges of unicode symbols you want to replace (e.g. \u017F-\036F\u0400-\uFFFF )
otherwise use a a class to specify what symbols don't need to be replaced, like a-z, accented/diacritic letters and greek symbols
string.replace(/[^a-z\00C0-\017E\u0370-\03FF]/gi, '*');

You have to use the XRegexp plugin, along with the Unicode add-on.
Once you have that, you can use modern regexes like /[\p{L}\p{Nl}]/, which necessarily also includes those \p{Greek} code points which are letters or letter-numbers. But you could also match /[\p{Latin}\p{Greek}]/ if you wanted.
Javascript’s own regexes are terrible. Use XRegexp.

So something like: /^[^?&\^"]*$/ (that means the string is composed only of characters outside the five you listed)...
But if you want to have the greek characters and the unicode characters (what are unicode characters? àèéìòù? Japanese?) perhaps you'll have to use http://xregexp.com/ It is a regex library for javascript that includes character classes for the various unicode character classes (I know I'm repeating myself) plus other "commands" for unicode handling.

Javascript regular expression for punctuation (international)?

I need a regular expression to match against all punctuation marks, such as the standard [,!##$%^&*()], but including international marks like the upside-down Spanish question mark, Chinese periods, etc. My google-fu is coming up short. Does anyone have such a regular expression on hand that's compatible with Javascript?

Adding to #stema's answer (https://stackoverflow.com/a/7578937/114140)... here is the regex as a string (so you don't need to bloat your project with XRegExp).
!-#%-\x2A,-/:;\x3F#\x5B-\x5D_\x7B}\u00A1\u00A7\u00AB\u00B6\u00B7\u00BB\u00BF\u037E\u0387\u055A-\u055F\u0589\u058A\u05BE\u05C0\u05C3\u05C6\u05F3\u05F4\u0609\u060A\u060C\u060D\u061B\u061E\u061F\u066A-\u066D\u06D4\u0700-\u070D\u07F7-\u07F9\u0830-\u083E\u085E\u0964\u0965\u0970\u0AF0\u0DF4\u0E4F\u0E5A\u0E5B\u0F04-\u0F12\u0F14\u0F3A-\u0F3D\u0F85\u0FD0-\u0FD4\u0FD9\u0FDA\u104A-\u104F\u10FB\u1360-\u1368\u1400\u166D\u166E\u169B\u169C\u16EB-\u16ED\u1735\u1736\u17D4-\u17D6\u17D8-\u17DA\u1800-\u180A\u1944\u1945\u1A1E\u1A1F\u1AA0-\u1AA6\u1AA8-\u1AAD\u1B5A-\u1B60\u1BFC-\u1BFF\u1C3B-\u1C3F\u1C7E\u1C7F\u1CC0-\u1CC7\u1CD3\u2010-\u2027\u2030-\u2043\u2045-\u2051\u2053-\u205E\u207D\u207E\u208D\u208E\u2329\u232A\u2768-\u2775\u27C5\u27C6\u27E6-\u27EF\u2983-\u2998\u29D8-\u29DB\u29FC\u29FD\u2CF9-\u2CFC\u2CFE\u2CFF\u2D70\u2E00-\u2E2E\u2E30-\u2E3B\u3001-\u3003\u3008-\u3011\u3014-\u301F\u3030\u303D\u30A0\u30FB\uA4FE\uA4FF\uA60D-\uA60F\uA673\uA67E\uA6F2-\uA6F7\uA874-\uA877\uA8CE\uA8CF\uA8F8-\uA8FA\uA92E\uA92F\uA95F\uA9C1-\uA9CD\uA9DE\uA9DF\uAA5C-\uAA5F\uAADE\uAADF\uAAF0\uAAF1\uABEB\uFD3E\uFD3F\uFE10-\uFE19\uFE30-\uFE52\uFE54-\uFE61\uFE63\uFE68\uFE6A\uFE6B\uFF01-\uFF03\uFF05-\uFF0A\uFF0C-\uFF0F\uFF1A\uFF1B\uFF1F\uFF20\uFF3B-\uFF3D\uFF3F\uFF5B\uFF5D\uFF5F-\uFF65
I used this in my own project with some additions...
// any kind of punctuation character (including international e.g. Chinese and Spanish punctuation)
// author: http://www.regular-expressions.info/unicode.html
// source: https://github.com/slevithan/xregexp/blob/41f4cd3fc0a8540c3c71969a0f81d1f00e9056a9/src/addons/unicode/unicode-categories.js#L142
// note: XRegExp unicode output taken from http://jsbin.com/uFiNeDOn/3/edit?js,console (see chrome console.log), then converted back to JS escaped unicode here http://rishida.net/tools/conversion/, then tested on http://regexpal.com/
// suggested by: https://stackoverflow.com/a/7578937
// added: extra characters like "$", "\uFFE5" [yen symbol], "^", "+", "=" which are not consider punctuation in the XRegExp regex (they are currency or mathmatical characters)
// added: \u3000-\u303F Chinese Punctuation for good measure
var regex_characters_to_remove = /[\$\uFFE5\^\+=`~<>{}\[\]|\u3000-\u303F!-#%-\x2A,-/:;\x3F#\x5B-\x5D_\x7B}\u00A1\u00A7\u00AB\u00B6\u00B7\u00BB\u00BF\u037E\u0387\u055A-\u055F\u0589\u058A\u05BE\u05C0\u05C3\u05C6\u05F3\u05F4\u0609\u060A\u060C\u060D\u061B\u061E\u061F\u066A-\u066D\u06D4\u0700-\u070D\u07F7-\u07F9\u0830-\u083E\u085E\u0964\u0965\u0970\u0AF0\u0DF4\u0E4F\u0E5A\u0E5B\u0F04-\u0F12\u0F14\u0F3A-\u0F3D\u0F85\u0FD0-\u0FD4\u0FD9\u0FDA\u104A-\u104F\u10FB\u1360-\u1368\u1400\u166D\u166E\u169B\u169C\u16EB-\u16ED\u1735\u1736\u17D4-\u17D6\u17D8-\u17DA\u1800-\u180A\u1944\u1945\u1A1E\u1A1F\u1AA0-\u1AA6\u1AA8-\u1AAD\u1B5A-\u1B60\u1BFC-\u1BFF\u1C3B-\u1C3F\u1C7E\u1C7F\u1CC0-\u1CC7\u1CD3\u2010-\u2027\u2030-\u2043\u2045-\u2051\u2053-\u205E\u207D\u207E\u208D\u208E\u2329\u232A\u2768-\u2775\u27C5\u27C6\u27E6-\u27EF\u2983-\u2998\u29D8-\u29DB\u29FC\u29FD\u2CF9-\u2CFC\u2CFE\u2CFF\u2D70\u2E00-\u2E2E\u2E30-\u2E3B\u3001-\u3003\u3008-\u3011\u3014-\u301F\u3030\u303D\u30A0\u30FB\uA4FE\uA4FF\uA60D-\uA60F\uA673\uA67E\uA6F2-\uA6F7\uA874-\uA877\uA8CE\uA8CF\uA8F8-\uA8FA\uA92E\uA92F\uA95F\uA9C1-\uA9CD\uA9DE\uA9DF\uAA5C-\uAA5F\uAADE\uAADF\uAAF0\uAAF1\uABEB\uFD3E\uFD3F\uFE10-\uFE19\uFE30-\uFE52\uFE54-\uFE61\uFE63\uFE68\uFE6A\uFE6B\uFF01-\uFF03\uFF05-\uFF0A\uFF0C-\uFF0F\uFF1A\uFF1B\uFF1F\uFF20\uFF3B-\uFF3D\uFF3F\uFF5B\uFF5D\uFF5F-\uFF65]+/g

If it's possible for you to use a plugin, there is a plugin for JavaScript: XRegExp Unicode plugins. That adds support for Unicode categories, scripts, and blocks (I personally have only read about it, I never used it).
With this plugin it should be possible to use Unicode categories like \p{P} as explained at regular-expressions.info.
Update:
OK, I tested it, and it seems to work fine.
You need to get the lib from XRegExp and additionally the Unicode Base and Unicode Category plugins (linked above).
<script src="xregexp.js"></script>
<script src="addons/unicode-base.js"></script>
<script src="addons/unicode-categories.js"></script>
<script>
var unicodePunctuation = XRegExp("^\\p{P}+$");
alert(unicodePunctuation.test("?.,;!¡¿。、·")); // true
</script>
The above alerts true. I included some Spanish and Chinese punctuation in my test string, "?.,;!¡¿。、·".

From ES 2018, Unicode property escapes are supported. You can use \p{Punctuation} or just \p{P} (the same as the XRegExp answer) to match any punctuation character (by the Unicode definition), or \P{Punctuation} to match any non-punctuation character.
If you want to match any "non-word" character, like a Unicode version of \W, you can try something like:
[^\p{Alphabetic}\p{Mark}\p{Decimal_Number}\p{Connector_Punctuation}\p{Join_Control}]
(as recommended in the proposal for the feature). You might want to remove \p{Connector_Punctuation}, since that includes underscores and similar.
Don't forget to add the u flag to your regular expression to make it Unicode-aware and enable this feature.

Well... idk how extensive it would be, but you could use this:
[^\w\s\n\t]

Your regex would look something like...
/[,!##$%^&*()\u9999]/
Where you replace each \u9999 with the Unicode codepoint for the other punctuation characters.
If you could find a bunch in a range, you could specify that with the - range operand, e.g. \u9990-\u9999.
As far as I know you can't use something like \pP in JavaScript regexes.

For Python this regex to remove from the start and end any type of punctuation marks:
import re
def cleanspecialcharacters(str):
regex = re.compile((
'^[/\"_\(\)&*\$￥\^\+=`~<>\{\}\[\]\|\-!#%\,\:;#¡§«¶·»¿;·՚-՟։֊؉،॥॰෴๏๚๛༄-༒༔༺-༽྅჻፠-፨᐀᙭᙮។-៖៘-៚‧‰-⁃⁅-⁑⁓-⁞⁽⁾₍₎、〃〈-【】〔-〟〰〽゠・﴾﴿︐-︙︰-﹒﹔-﹡﹣﹨﹪﹫！-＃％-＊，-／：；？＠［-］＿｛｝｟-･〔〕《》]*|'
'([/\"_\(\)&*\$￥\^\+=`~<>\{\}\[\]\|\-!#%\,\:;#¡§«¶·»¿;·՚-՟։֊؉،॥॰෴๏๚๛༄-༒༔༺-༽྅჻፠-፨᐀᙭᙮។-៖៘-៚‧‰-⁃⁅-⁑⁓-⁞⁽⁾₍₎、〃〈-【】〔-〟〰〽゠・﴾﴿︐-︙︰-﹒﹔-﹡﹣﹨﹪﹫！-＃％-＊，-／：；？＠［-］＿｛｝｟-･〔〕《》])*$'))
str = regex.sub('', str)
return str