Regex latin characters only. ç becomes c. The search function takes both strings and regexes, so the / are necessary to specify a regex. To allow only characters in the Basic Latin character set, which includes standard English lanuage punctuation (i. Latin characters are covered by \w. Think of it as a suped-up text search shortcut, but a regular expression adds the ability to use quantifiers, pattern collections, special characters, and capture groups to create extremely advanced search May 27, 2015 · The Hebrew Unicode adds a lot of punctuation and symbols (as you can see in the table here) irrelevant for such validation. 9, or . Nothing after / - close expression; i - the expression is case insensitive; tested with the following cases Jun 23, 2017 · I am trying to match any string that contains either only Basic Latin (ASCII) characters or only Greek Unicode characters. May 30, 2012 · E. answered Apr 14, 2012 at 11:55. answered Jun 6, 2016 at 13:01. List of Spcl char: var listAdvSpclChar = File. NET supports the following character classes: Positive character groups. and so on, but things like ‡ or Ω or ‰ just get striped away. This matches on only one or more characters in the given ranges and will fail if any other character is encountered. isalnum() print isEnglish('slabiky, ale liší se podle významu') print isEnglish('English') print isEnglish('ގެ ފުރަތަމަ ދެ އަކުރު ކަ') print Mar 8, 2012 · Possible Duplicate: Regular expression to match non-english characters? I am using this regex to limit some characters. IsLetter. I am not clear now how to do it with a regular expression. 1. *, meaning: every character (except newline chars) zero to unlimited times. \s_-]+$ ^ asserts that the regular expression must match at the beginning of the subject [] is a character class - any character that matches inside this expression is allowed; A-Z allows a range of uppercase characters; a-z allows a range of lowercase characters. Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java, C#/. 4/6 I already covered. , the characters that can be directly entered on a U. ddd" with space "before the DOT" and with deleting the Tag "@aaa". In character classes, most escape sequences are supported, except \b, \B, and backreferences. \P{Cc}\P{Cn}\P{Cs}: Match only non-control characters that have been assigned and are UTF-8 valid. The last character has to be an alphanumeric character. Pattern. Dec 11, 2019 · 1. The following additional characters: space, period (. Cyrillic Extended-A: U+2DE0–U+2DFF, 32 characters. A locale can provide others. – Oct 26, 2013 · @AlanMoore Regarding \W and it matches only ASCII, this not problem we build passwords for Latin English keyboard in general, so any other character rather than \w|\d should be regarded a special character including other languages alphabets. Do Mar 26, 2021 · The reason why the current regex isn't working: /(\w. Here's again a Java example: I need to check a string containing only a. move it inside the character class, where it no longer needs to be escaped, giving @"[a-zA-Z. 05-18-2023 12:42 PM. – Yes, the original set of Unicode characters (C0 and Basic Latin block) you cite includes the letters of the English alphabet but is insufficient for English text. So result will be this. Jun 7, 2010 · If numbers are ok, too, you can shorten this to. In that case, you can get all alphabetics by subtracting digits and underscores from \w like this: \A[^\W\d_]+\z. - at the end of the character class matches a single hyphen. I'm forcing a field in a UI to match the format: last_name, first_name (last [comma space] first) Feb 12, 2013 · Note that characters like +,(,),* etc. Another approach: instead of cutting away part of the fields' contents you might try the SOUNDEX function, provided your database contains European characters (i. Special characters ( _, , -) have to be followed by an alphanumeric character. So in the example above I wanted to return "Afds". Nov 23, 2014 · If you work with strings (not unicode objects), you can clean it with translation and check with isalnum(), which is better than to throw Exceptions: . Aug 8, 2011 · 4. ddd". ([^\x00-\x7F]|\w)+. RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp). I just had my mind blown over at Stack Overflow. It does not enforce that the string contain only non-letters. You can change the asterisk (*) to a question mark (?) if you want to allow at most one dash (e. This is treated as a range of all the characters from * to _ i. Using a Venn diagram on the back of an envelope helps. You want this: Regex strPattern = new Regex("^[0-9A-Za-z_]*$"); Your expression does not work because: It will accept any number of digits, followed by any number of uppercase letters, followed by any number of lowercase letters, followed by any number of underscores. Numbers are not required to be in Arabic. Also note: that this works for only a-z, A-Z. Apr 19, 2015 · 88. just joking, it answers the question but, in any case, ^[abcdefghijklmnopqrstuvwxyz][_abcdefghijklmnopqrstuvwxyz0-9]{2,17}$ is one butt-ugly regex :-) – Depends on the task :-) To match exactly all Latin characters and their accented versions, the Unicode ranges probably provide the best solution. This (|) is logical or and \w is english letter, so ([^\u0000-\u007F]|\w) will match single english or non-english letter. 3. This includes Japanese ideographic characters. The site is translated into a number of languages, but due to the regulatory procedures, we have to force users to input … Continue reading PHP regular expression to match English/Latin characters only Dec 26, 2013 · [a-z] - find only one character between a to z, including [a-z0-9]* - find any sequence of characters either between a to z including, or between 0-9 including (the "any sequence" part is the * in the end) $ - string must end here. Do so by checking for anything that matches the complement of the valid alphanumeric string. Jun 5, 2012 · Look at the section "Unicode support", particularly the references to the Character class and to the Unicode Standard itself. Below you find a short version which matches all characters not in the range from A to Z and replaces them with the empty string. Ah, you'ved edited your question to say the three alphabet characters must be consecutive. The regex matches: ^ - start of string [A-Z@~`!@#$%^&*()_=+\\\\';:\"\\/?>. You can match any character in one of these scripts using \p{Han}, \p{Hiragana}, \p Oct 27, 2018 · Try this regex, ([A-Z]+)[^A-Z]* This regex captures all continuous capital letters in group 1 and optionally consumes any non-capital letters, thus giving you capital alphabets only in group 1 in the regex. This regex pattern ensures that the string consists of one or more uppercase or lowercase letters or space. Aug 18, 2011 · We have have a site with some user registration forms. Nov 24, 2015 · See regex demo. S. which accepts only only Arabic characters while I need Arabic characters, Spaces and Numbers. Oct 9, 2023 · In general, we have two main approaches to this problem. compile ("\u00E0") will match both the single-code-point and double-code-point encodings of à Apr 18, 2012 · Regex condition string contains English AND NOT Greek or vice versa (Greek and not English) only 0 How to write a custom function to semi-automate column naming when converting a data object to dataframe Apr 26, 2016 · This regex will do the following: Assume words are entirely made up of alphabetical characters A-Z, upper case and lower case; Find all words; Ignore all strings that contain non-alphabetical characters or symbols; Assumes some punctuation like periods or commas are to be ignored but the preceding word should be captured. \P{Cc}\P{Cn}: Match only non-control characters that have been assigned. Sep 11, 2019 · You shouldn't put \p{L} into character set (inside []), it looses its meaning and in the end you just added {} to the list of characters to match. , \p{L} (and its shorthand, \pL) matches any letter in any language. +/gi It matches a word; followed by any character (1 or more) followed by a whitespace character; followed by any character (1 or more) Since the input Åäö doesn't contain a valid word character (according to regex), it already fails due to the first rule. Explanation: \p{L} is a shorthand for the Unicode property "Letter". org Learn how to create a regular expression to validate a string that contains only Latin characters, including a space. Dec 26, 2018 · 1. Why not add a Unicode range for all Latin characters to your regex? r"[\u00C0-\u017F]" Will match all your diacritically enhanced Unicode characters using Latin based alphabets. 4 days ago · First, this is the worst collision between Python’s string literals and regular expression sequences. But it does not include, e. Your regex matches whitespace and hence split occurs at each occurrence of one or more whitespace. \p{IsLatin} will match those characters without matching characters from other, non-Latin alphabets. ( I need special character only for the middle name) So I tried following regular Dec 30, 2021 · Create a character class for letters, digits and whitespace patterns ( /^\p{Latin}+$/u => ^[\p{Latin}]+$/u) Then add the digit and whitespace patterns. I want Regular Expression to accept only Arabic characters, Spaces and Numbers. Not sure if that harms. Dec 28, 2020 · Here the string has datatype nchar, 'letters' specifically refer to latin characters. Use ^[[:alpha:]] See what the docs say: Standard character class names are: alnum, alpha, blank, cntrl, digit, graph, lower, print, punct, space, upper, xdigit. Just a shot in the dark, but check if adding more backslashes will work, making it \\!\\\". Cyrillic Supplement: U+0500–U+052F, 48 characters. You need to either put the - at the beginning or end of the set, or escape it within the set e. . * There is an exception to this rule. keyboard). Regular Expression to a-z A-Z latin characters and blank space. If you need to support only ASCII digits, add 0-9. I want to use those special character as Regex. matches("\\w+"); This by the way also covers numbers and the underscore _. Character classes. They might be extended to all non-whitespace characters, which could be done using the \S character class. I need regex to validate Firstname and Lastname fields. Jul 10, 2014 · Accented Characters: DIY Character Range Subtraction. -] \w is supported in many modern regex engines, but not universal. To match any letter other than an ASCII letter, you can use [^\P{L}a-zA-Z]. translate(None, string. sub, for performance consider a re. As it turns out, regular expressions have a mechanism to match entire Unicode categories, including values to specify entire Unicode "scripts", each corresponding to groups of characters used in different writing systems. Else you can just use [A-Za-z]+ instead. Of course, if you're using straight ASCII characters than any of the aforementioned regular expressions will work. I'm assuming from your third sentence that you don't want underscore. punctuation). Here's a Java example: boolean valid = string. +\s). Some of the answers out there seem to check the first character in the text field Mar 13, 2017 · Your first two sentences contradict each other. If that's right, you can easily exclude them from your RegEx. Using Regex. To use \ literally, escape it as \\. Mar 28, 2017 · Matching Latin Characters with Regular Expressions. Full RegEx Reference with help & examples. matches("\\p{L}+"); Alternatively, you could also normailze the text to get rid of the diacritical marks and check if it contains [A-Za-z]+ only. don't have any special meaning inside a character class. g. Since \w includes the underscore, your regex did allow Apr 25, 2012 · I figured out that the Solutions with regex are 30 times slower than the ones with the Char. Roll over a match or expression for details. All reactions Nov 21, 2016 · The POSIX character class [:alpha:] is locale-dependent and matches Unicode letters as well. I have this one: Aug 27, 2013 · That is to say, \w matches only Latin letters, decimal digits, and underscores ([a-zA-Z0-9_]), and \b matches the boundary the between a word character and and a non-word character. I wanted to change this to allow all latin and non-latin letters but i t 5. I also see that you may want to enforce that all characters should match one of your "accepted" characters. [\w. only a or a-a). \b indicates a backspace character instead of a word boundary, while the other two cause syntax errors. ]" Your second issue, as Benoit points out, is that your regular expression is asking "does any character matching this class exist anywhere in the input", where Oct 25, 2012 · In . Due to /i modifier, you do not have to specify a-z range in the character class as case-insensitivity is enabled. For example consider this Jun 29, 2015 · Instead of checking for a valid alphanumeric string, you can achieve this indirectly by checking the string for any invalid characters. IsLetterOrDigit check. *[a-z]){3}/i. In this case I just want "BCAD". z, 0. To match only Russian Cyrillic characters use: [\u0401\u0451\u0410-\u044f] which is the equivalent of: [ЁёА-я] where А is Cyrillic, not Latin. string str = "Abcáàéèó"; bool result = str. If you must ensure that no non-letter characters are matched, anchor the regex like ^[^A-Za-z]+$ -- I think that's what you are asking. @Fredrik Mörk: I guess that is obvious. Consider following ranges: Cyrillic: U+0400–U+04FF, 256 characters. ReadLines(_spclCharFilePath, Encoding. yxmd. If you’re not using raw strings, then Python will convert the \b to a backspace, and your RE won’t match as you expect it to. ) Feb 28, 2013 · 7. Jun 22, 2016 · In the world of regular expressions, matching characters outside of the usual Latin character set can be a challenge. 412?A returns False //'?' is neither a letter nor a number. <, >, + or $ which is important for security. Unicode scripts are not supported by . (Despite looking the same they have different codes) \p{IsCyrillic}, \p{Cyrillic}, [\u0400-\u04FF] which others suggested will match all variants of Cyrillic, not only Russian. IsLetterOrDigit function. "The following regex matches alphanumeric characters and underscore" doesn't limit it to Latin letters. NET, is equivalent to your regex, additionally allowing other Unicode letters. Jun 27, 2023 · Show 11 more. ^ in the character classes negates the character class, so that the regex will match the opposite of the character class (anything you do not specify). But the regular expression should look like this: ^ and $ denote the begin and end of the string respectively; [a-zA-Z0-9] describes one single alphanumeric character and {6,} allows six or more repetitions. Feb 10, 2010 · Instead of fiddling with regular expressions try changing for the NVARCHAR2 datatype prior to character set upgrade. Thanks in advance. However, the same syntax \uFFFF is also used to insert Unicode characters into literal strings in the Java source code. should be sufficient. This is a negated character class that matches any chars other than a non-letter char (\P{L}) and ASCII letters (a-zA-Z). regex. The regular expression language in . Nov 6, 2013 · You either need to. Results update in real-time as you type. ", or. The Letter category includes letters from all kinds of languages, not just A-Z. If you insist on a regular expression you are almost there: use ^[A-Za-z0-9]+$. /[^a-z\d]/i. e. ), apostrophe ('), and space. Supports JavaScript & PHP/PCRE RegEx. Mentioned by @AnthonyFaull you may want to consider matching \p{IsLatinExtendedAdditional} as well which is a named block for U+1E00-U+1EFF that Sep 12, 2023 · The only characters that cannot appear literally are \, ], and -. (The case-insensitive modifier means that we don't need to look at uppercase letters, too. If you need to support any Unicode digits, add \d. IsLetter Method. For a non-REGEX solution you can use char. Apr 24, 2019 · I am trying to check text with regular expression and i need to check if it contains only letters, spaces and also non english characters. From the MDN Docs, the function returns -1 if there is no match. HI All, I am having a mental block I have the following formula if isempty ( [_CurrentField_]) then 'UT' elseif. ê becomes e. "in \w but is not in \d " includes underscore. Sep 13, 2012 · See re. but that would be slow. These stand for the character classes defined in ctype. split does is that it splits the string at patterns matching the regex. I've done some searching but only found the built-in ISNUMERIC() function, which is for numbers only. Database environment is Microsoft SQL Server 2014. I could iterate over each character and check the character is a. – BrockLee. Perhaps you should include ê and ff, too. Read on to find out how author Mark Needham tackled this issue in Python. May 24, 2013 · Bulletproof right up until the point where you stop assuming everyone on the planet has an English name, and you want to allow non-Latin characters. @Smccullough: no need for escaping inside a character class, except for ] and `\`. import string def isEnglish(s): return s. Just use \p{L} . \A matches at the start of the string, \z at the end of the string ( ^ and $ also match at the start Aug 5, 2012 · What I wanted to do using regex is to start from the left, return characters A-Z || a-z until an unmatached is encountered. So far I just have a basic string regex. My problem is, the regex work in detecting the latin characters, but nothing is applied from the regex set on the text. in Regex101 it works fine for javascript. Smccullough. "^[a-zA-Z0-9_]+$" fails. Undo & Redo with {{getCtrlKey()}}-Z / Y in editors. Then it comes to mind that you are talking about Cyrillic characters. z or 0. So for the \\\", you have 2 backslashes to get one \` and another backslash to get "`. If you want to restrict your requirements further, you will likely need to define your own (lenghty) character class with specific Spanish characters. The Regex Feb 10, 2021 · You have to decide what English characters means, and how many false negatives you can live with. So this should do: boolean valid = input. \P{Cc}: Match only non-control characters. For example, [abcd] is the same as [a-d] . mozilla. Oct 20, 2017 · Note that you will still have some non-Spanish characters in the Latin 1 supplement, see here. Nov 11, 2008 · Note that you will need to exclude the high-end characters, as JavaScript can only handle characters less than FFFF (hex). Indicates whether the specified Unicode character is categorized as an alphabetic letter. Apr 14, 2022 · By Corbin Crutchley. Cyrillic Extended-B: U+A640–U+A69F Jan 17, 2009 · I need a generic transliteration or substitution regex that will map extended latin characters to similar looking ASCII characters, and all other extended characters to '' (empty string) so that é becomes e. + at the end of the expression means it could be repeated, so the whole expression allows all english or non-english Jan 8, 2020 · Some regex engines don't support this Unicode syntax but allow the \w alphanumeric shorthand to also match non-ASCII characters. Let's look at what we DON'T want: (1) characters that are not matched by \w (i. Note though that this does not match the letter 'ö', amongst others. For example, an underscore followed by a number would not match. it should be like "bbb các . I suggest checking the Abbreviate Collate, and Escape check boxes, which strike a balance between avoiding unprintable characters and minimizing the size of the regex. Nov 22, 2010 · What is a regular expression that accepts only characters ranging from a to z? Skip to main content. Validate patterns with suites of Tests. Regular Expression: Allow only characters a-z, A-Z. I would consider adding ' (single quote) as well, for foreign consonants that are missing in Hebrew (such as G in Oct 3, 2022 · I'm new to regexp. But it produces the same input text!: "@aaa bbb các. "); } The / starting and ending the regular expression signify that it's a regular expression. Latin-1) characters only. This is for use with a JavaScript function. Default); StringBuilder sb = new StringBuilder(); foreach (string s in listAdvSpclChar) Mar 11, 2013 · To enforce three alphabet characters anywhere, /(. Dec 3, 2008 · "I would like to have a regular expression that checks if a string contains only upper and lowercase letters, numbers, and underscores" doesn't limit it to Latin letters. To find all words in an input string using Latin or Cyrillic, you'd have to do something like this: Aug 23, 2021 · Regular Expression - letters, apostrophes, full stops, commas and hyphens are allowed 0 How to match regular expressions only if they are surrounded with proper punctuation characters in Javascript? Apr 14, 2012 · Depending on the regex engine, you may be able to use: ^\p{IsBasicLatin}*$. The above would match any lower-cased alphabetical Latin character or ^. Caveat: I think you wanted to not allow the underscore as initial character (evidenced by its presence only in the second character class). @Masond3 The below regex checks for all the ASCII characters and Latin letters. -]+$/ following strings are also accepted: tavish. If you want to cover diacritical characters as well (ä, é, ò, and so on, those are per definition also Latin characters), then May 18, 2023 · 20 - Arcturus. – May 3, 2019 · This [^\x00-\x7F] and this [^\u0000-\u007F] parts allow regullar expression to match non-english letters. I have 6 steps for password. Example for desired result: C172E returns True. *, +, , ], ^, _ (I've left out the rest of the characters for brevity). The Mark category – as lionelrowe pointed out in the comments (thanks) – contains Nov 6, 2013 · You see true because it matches solely on the . People can have 2 names for example so it should be able to handle multiple non latin words. Oct 8, 2012 · Regex: Only 1 space but not at the start, no numbers/special characters, any string before or after space needs to have at least 2 alphabetic chars 1 How to match all word which starts with a space and character Jul 30, 2013 · I don’t know any partial bandaide for Javascript’s horrendous Unicode non-handling that doesn’t involve XRegExp, and even that is a far, far cry from the most basic, level-1 compliance with the published gold standard for this sort of thing, UTS 18: Unicode Regular Expressions. isascii() is perhaps the easiest, but will choke on many English words. Apr 12, 2022 · So if you ever need a regular expression to verify whether a name has been inputted correctly for instance, and you want it to allow only Latin characters and accents, here's a solution: \^([A-Za-z See full list on developer. I found the following expression: ^[\u0621-\u064A]+$. I'm trying to figure out how to allow only Latin letters, prohibit spaces, but so that my other regexps still work. 9, and . Because Javascript sucks so bad at Unicode, that forces you Regular expression tester with syntax highlighting, PHP / PCRE & JS Support, contextual help, cheat sheet, reference, and searchable community patterns. I need to validate an input so that it matches only these criteria: Letters A-Z (upper and lowercase) Numbers 0-9. I have this regular expression which matches the exact opposite (all strings that contain at least one greek and one latin character), but cannot find a way to Feb 22, 2019 · 11. The only thing different is what you allow in the character class that the quantifier applies to. @Marcus The pattern looks for any character other than upper/lower letters, and your single whitespace matches. ), comma (,), plus (+), and dash (-) I can write a pattern easily enough for the first two criteria, but the third one is more difficult. <,-]* - 0 or more characters inside the A-Za-z range and all the special ASCII characters (you can add more if I missed any or if you need to Jul 6, 2016 · I have list of character which contains both normal special character as well as Latin Extended character. @loldop: This will match anywhere in the string, and only one character. The longhand version will work way back to the original Thompson regex engine. Sep 8, 2019 · Also, escaping the ^ symbol in a character class is only necessary if it is the first character in the character class. Char. Reply. It's just like matching multiple Latin characters: [a-z]+ or [a-z]{3} or even [a-z]{2,10}. Edit. compile to optimize the pattern once. Thus, you can use. 1. Jan 6, 2010 · In a full fledged regex environment you could just test if the string matches \p{L}+. The first uses a regex pattern, and the second checks all the characters individually. Having that said, you are able to match all latin characters using below regex: or simply use ^[\u0000-\u024F0-9]+$. , by putting a \ in front of it, giving @"[a-zA-Z]|\. NET regex engine but Unicode blocks are. . In our case, we’ll be using this one: String REGEX = "^[a-zA-Z0-9]*$"; May 19, 2015 · Basic Latin (excluding the C0 control characters), Latin-1 (excluding the C1 control characters), Latin Extended A, Latin Extended B and Latin Extended Additional. A Regular Expression – or regex for short– is a syntax that allows you to match strings with specific patterns. Most Latin characters, like ë, ɶ, or ṧ, can only be represented by Unicode. don't want anything that's not alpha, digits Oct 20, 2021 · I understand that by "a non-latin character such as הּ" you mean any non-ASCII letter. Mar 2, 2018 · I got a reference from the link: Javascript validation to allow only Alpha characters, hyphen (-), dot (. A character class defines a set of characters, any one of which can occur in an input string for a match to succeed. Do not match any control or unassigned characters. From there, just add the rest of your parameters of what you are looking for. True, and depending on the regex flavor and settings, \w may also match Unicode letters, which may or may not be desirable. Java 7 supports Unicode scripts, including the Hiragana, Katakana, Han, and Latin scripts that Japanese text is typically composed of. – To elaborate a bit, in case this is a point of confusion, Latin != ASCII. If you had any additional characters, just add the ^ anywhere else and it will work as expected [a-z^] Reference. Do not match any invisible characters. But with the regex /^[a-zA-Z '. drf. Here is an example: var alphanumeric = "someStringHere"; Jan 12, 2015 · The regular expression accepts at least one English letter, and then naught or more of one dash and at least one letter. All(char. Ď becomes D. Do not match any control characters. And I have exactly the same requirement. Regex_Latinletters_180523. Your problem is the *-_ inside your character set. But have problems with the remaining 2 steps. We were not sure that those Letters or Digits include and we were in need of only Latin characters so implemented our function based on the decompiled version of Char. matches a period rather than a range of In Java, the regex token \uFFFF only matches the specified code point, even when you turned on canonical equivalence. Oct 4, 2023 · Character class: Matches any one of the enclosed characters. 0. What pattern. – May 16, 2015 · I'm looking to included the Latin characters below in a JavaScript regex for a string validation. NET, Rust. If I enter: JĀNIS BĀNIS for example, it doesnt work! javascript. That allows a, a-a, a-a-a, and so on (using a to stand for at least one capital or lower-case letter). Here is our solution: Dec 1, 2017 · The regex you're looking for is ^[A-Za-z. If your regex engine allows it (and many will), this will work: Regular expression that accepts only alert("There are non characters. In Python’s string literals, \b is the backspace character, ASCII value 8. If it works, tell me so I can update my answer please. A character in the input string must match one of a specified set of characters. á becomes a. example: if I have a text like "@aaa bbb các. Nov 21, 2019 · You can add more to the RegEx outside of these boundaries for things like appending/prepending a required suffix or prefix. Is this correct? Can you suggest a simpler regular expression or a more efficient approach. Not allowing strings with mixed characters from these two sets. Use Tools to explore your results. IsLetter); This would give false result for digits and \/<>*() etc. This set corresponds to Unicode code points U+0020 to U+007E, U+00A0 to U+024F and U+IE00 to U+IEFF. This is the simplest approach, which requires us to provide the correct regex pattern. The ] character indicates the end of the Jun 22, 2015 at 13:41. Save & share expressions with others. [a-z]* This part says to look for all lowercase letters. (period) and no other character. This is what I have for validatating latin+non-latin characters, but it doesn't support multiple words. If you want only Hebrew letters (along with English letters) the regex would be: /^[a-z\u05D0-\u05EA]+$/i. Sep 20, 2010 · If you remove the use utf8 then none of the regular expressions match. Jun 6, 2016 · Visualized with Regexper: As you can see a user name always has to start with an alphanumeric character. You can specify a range of characters by using a hyphen, but if the hyphen appears as the first or last character enclosed in the square brackets, it is taken as a literal hyphen to be included in the character class as a normal character. \p{L} - matches a single Unicode Code Point in the 'Letters' category (see the Unicode Categories section here ). escape the . Beyond that, you can use a regex matching specific character classes or groups, and accept eg words that only have Latin characters with eg [^\p{IsLatin}]. any character except newline \w \d \s: word, digit, whitespace Mar 8, 2021 · In Unicode, all characters are sorted into categories that we can use in our regular expression. Looking at this very relevant question , it looks like you probably want to use utf8 and check out Unicode::Semantics . dt ns dk cz zw qc sy ap zi sp