Regular expression backslash

The backslash \ is the escape character for regular expressions. Therefore a double backslash would indeed mean a single, literal backslash. \ (backslash) followed by any of [\^$.|?*+ () {} escapes the special character to suppress its special meaning 15.7 Backslash in Regular Expressions. For the most part, '\' followed by any character matches only that character. However, there are several exceptions: two-character sequences starting with '\' that have special meanings. The second character in the sequence is always an ordinary character when used on its own Note that, to match a backslash verbatim, in accordance with JavaScript regular expression syntax you need two backslash characters in your regular expression literals such as /\\/ or /\\/g. When calling a RegExp constructor, you have to double each of the two backslashes in the string argument passed to the constructor, like this: \\\\ So regex which we are trying to create is \\. But to create string representing \\ so you could pass it to regex engine you need to write it as four \ (\\\\), because \ is also special character in String (it can be used for instance as \t to represent tabulator) so you also need to escape both \ there. In other words you need to escape \ twice

Can't escape the backslash with regex? - Stack Overflo

15.7 Backslash in Regular Expressions - GN

  1. It has two uses in regular expressions: To denote the start of the line If used immediately after a square bracket ([^) it acts to negate the set of allowed characters (i.e. means the character 1, 2, or 3 is allowed, whilst the statement [^123] means any character other than 1, 2, or 3 is allowed
  2. In the regex flavors discussed in this tutorial, there are 12 characters with special meanings: the backslash \, the caret ^, the dollar sign $, the period or dot ., the vertical bar or pipe symbol |, the question mark ?, the asterisk or star *, the plus sign +, the opening parenthesis (, the closing parenthesis ), the opening square bracket [, and the opening curly brace {, These special characters are often called metacharacters
  3. As we've seen in Chapter 1, Introducing Regular Expressions, the backslash character \ is used to indicate metacharacters or special forms in regular expressions. The backslash is also used in strings to escape special characters. In other words, it has a special meaning in Python

In a regular expression, the backslash can perform one of two tasks: it either takes away the special meaning of the character following it (for instance, \| matches a vertical bar, it's not an alternation), or it is the start of a backslash or escape sequence In a regular expression a backslash (\) is used to escape a special characters so that they will be interpreted literally in the pattern. For example, the full stop character (.) has a special meaning - it means any character To get a regular expression escape, you need to have two backslashes. If you really want a backslash in the regular expression, you'll need four. The pattern recall would therefore be \\1 (you really want \1 in the string, so you have to escape it for SKILL), and then four backslashes either side of that To create that regular expression, you need to use a string, which also needs to escape \. That means to match a literal \ you need to write \\\\ — you need four backslashes to match one! x <- a\\b writeLines ( x ) #> a\b str_extract ( x , \\\\ ) #> [1] \\

Regular Expressions in QTP in Testing

Tcl Word Boundaries. Word boundaries, as described above, are supported by most regular expression flavors. Notable exceptions are the POSIX and XML Schema flavors, which don't support word boundaries at all. Tcl uses a different syntax.. In Tcl, \b matches a backspace character, just like \x08 in most regex flavors (including Tcl's) Backslash Constructs in Regular Expressions. For the most part, '\' followed by any character matches only that character.However, there are several exceptions: certain sequences starting with '\' that have special meanings.Here is a table of the special '\' constructs. specifies an alternative. Two regular expressions a and b with '\|' in between form an expression. The backslash (\) in a regular expression indicates one of the following: The character that follows it is a special character, as shown in the table in the following section. For example, \b is an anchor that indicates that a regular expression match should begin on a word boundary, \t represents a tab, and \x020 represents a space Answer. When a string is double quoted, it is processed by the compiler and again at run-time. Since a backslash (\) is removed whenever the string is processed, the double-quoted string needs double backslashes so that there is one left in the string at run time to escape a special character

The backslash is a metacharacter in regular expressions, and is used to escape other metacharacters. The regex \\ matches a single backslash. \d is a single token matching a digit. Python strings also use the backslash to escape characters. The above regexes are written as Python strings as \\\\ and \\w In a regular expression, character is a normal XML character that is not a metacharacter. metacharacters Metacharacters are control characters in regular expressions. The regular expression metacharacters that are currently supported are: backslash (\) Begins a character class escape For example, the regular expression Jack|Jill matches Jack and Jill. \ (backslash) The backslash symbol acts as an escape sequence. Use it when you want search for a regular expression symbol. The backslash character immediately precedes the symbol in the expression. For example, the regular expression a.\+.b matches the string a + b. A regular expression (regex) defines a search pattern for strings. If you want to define \w, then you must be using \\w in your regex. If you want to use backslash as a literal, you have to type \\\\ as \ is also an escape character in regular expressions. 4. Using regular expressions with String methods I want to backslash a variable automatically so that the end users don't need to type the backslashes for a Perl regex string replacement. Browse other questions tagged bash regular-expression perl escape-characters or ask your own question

The caret (^) at the beginning of a regex represents the beginning of a line. But that is not the case here. Within character class brackets here, it represents negation. We are looking for not a backslash. Now keep in mind that backslash is a special escape character within regex, so to use it as a literal, it must be escaped, hence the double backslash About Regular Expressions. A regular expression is a group of letters, numbers, and special characters used to match data. You can use Perl-compatible regular expressions (PCRE) in your Firebox configuration to match certain types of traffic in proxy actions Re: Regular Expression: Get all after a backslash. Jump to solution. Pattern \\ (.*) matches a backslash followed by zero to unlimited number of characters. The capturing group () is not necessary, \\.* would do the same here. Use positive lookbehind (?<=\\) to match only the characters after the backslash by extract function Regular expressions do not strictly limit the set of characters of the output result, i.e. the recognized value may contain characters which are not included into the regular expression. During recognition all hypotheses of a word recognition are checked against the specified regular expression

Most regular expression functions support an optional parameters argument as the very last input. The parameters argument is a VARCHAR string that specifies the matching behavior of the regular expression function. The following parameters are supported: Parameter. Effect The regular expression [A-Z] [a-z]* matches any sequence of letters that starts with an uppercase letter and is followed by zero or more lowercase letters. The special character * after the closing square bracket specifies to match zero or more occurrences of the character set The most basic expression is the backslash. Google Analytics ascribes this meaning to it: escape any of the above. What they mean is, you can use a backslash to turn any special character into a not-so-special character. Google (and everyone else who talks about Regular Expressions) makes this hard by using the word escape, when they merely mean, use a backslash to take the magic out of. Hi, I ave used a couple of regular expression before with C# and VB, but I just noticed a problem and I would like to know if there's a solution or at least an explanation. in regex, the backslash is a special character my problem is this : I have a string containing 2 backslah represented that · In C# one can have the contents of a.

Backslash in JavaScript Regular Expression

Backslash Expressions. Backslash Expressions are a simple substitute for Regular Expressions that work in some simple use cases.. Note: Backslash Expressions and Regular Expressions should not be used together, as one will override the other. Synta Issue Escaping a backslash in a parameter does not work as expected when regular expression is used in custom SQL in Google BigQuery. For example:-Sample data [Table]: Column aa a.-Custom SQL: select * from Table where regexp_contains(Column,r<parameter> The backslash in a regular expression precedes a literal character. You also escape certain letters that represent common character classes, such as \w for a word character or \s for a space Regular Expressions. A regular expression, or regexp, is a way of describing a set of strings.Because regular expressions are such a fundamental part of awk programming, their format and use deserve a separate chapter.. A regular expression enclosed in slashes (`/') is an awk pattern that matches every input record whose text belongs to that set Regular Expressions in SciTE Purpose. Regular expressions can be used for searching for patterns rather than literals. For example, it is possible to search for variables in SciTE property files, which look like $(name.subname) with the regular expression: \$([a-z.]+) (or \$\([a-z.]+\) in posix mode)

정규 표현식(正規表現式, 영어: regular expression, 간단히 regexp 또는 regex, rational expression) 또는 정규식(正規式)은 특정한 규칙을 가진 문자열의 집합을 표현하는 데 사용하는 형식 언어이다. 정규 표현식은 많은 텍스트 편집기와 프로그래밍 언어에서 문자열의 검색과 치환을 위해 지원하고 있으며, 특히. RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp). Supports JavaScript & PHP/PCRE RegEx. Results update in real-time as you type. Roll over a match or expression for details. Validate patterns with suites of Tests. Save & share expressions with others A backslash (\) followed by a single character other than new line matches that character. The caret (^) matches the beginning of a line. The A regular expression followed by an asterisk (*) matches a sequence of zero or more occurrences of the regular expression 20.2. Dealing with Escape Sequences (\) Escape sequences are a little tricky in C++ regular expressions, because they occur in two contexts. C++ assigns special meaning to the backslash within a string literal and requires it to be escaped to be read as an actual backslash: To represent a single backslash, it's necessary to place double backslashes (\\) in the source code As explained above, the Tcl 8.1 regular expression engine now interprets backslash sequences like \n to mean newline. It also has four new kinds of escapes: character entry escapes, class shorthand escapes, constraint escapes, and back references. Here's an introduction. (The re_syntax (n) page has full details.

regex - Java - regular expression to match a backslash followed by a quote - Stack

A regular expression is a pattern that is matched against a string from left to right. An escaping backslash can be used to include a whitespace or # character as part of the pattern. If you want to remove the special meaning from a sequence of characters, you can do so by putting them between \Q and \E Learn Javascript | The Backslash (Regular Expressions)Subscribe: http://bit.ly/2Pu3w4EGet your Patreon membership:https://www.patreon.com/calmandcodeIn this.

regex - Regular expression to allow backslash in C# - Stack Overflo

  1. The expression \$ matches a literal dollar sign because the backslash cancels the special meaning. When you use the Search and Replace String function in Regular Expression mode, you can specify a backreference in the replace string input that refers to submatches in the search string input
  2. Regular Expressions Every R programmer Should Know. Regular expressions. How they can be cruel! Well we're here to make them a tad easier. To do so we're going to make use of the {stringr} package. We're going to use the str_detect () and str_subset () functions. In particular the latter
  3. Provided by: perl-doc_5.32.1-3ubuntu2_all NAME perlrebackslash - Perl Regular Expression Backslash Sequences and Escapes DESCRIPTION The top level documentation about Perl regular expressions is found in perlre. This document describes all backslash and escape sequences
  4. Regular expressions (string, string1) A regular expression in a FIND, CHANGE, or EXCLUDE command allows you to search for a string matching a regular expression. ISPF uses the IBM® C regcomp and regexec functions to compile and execute a regular expression specified with a FIND, CHANGE, or EXCLUDE command
  5. Regular expression: backslash inside bracket . Jeppe Sommer. Ranch Hand Posts: 270. posted 9 years ago. Number of slices to send: Optional 'thank-you' note: Send. Hi. I want to make a regular expression which allow the user to type a slash and a backslash in the word. If I put a backslash inside the bracket it won´t work (compile)
  6. Regular Expressions. Regular expressions are special characters that match or capture portions of a field. This sections covers special characters supported by Check Point and the rules that govern them. In R70 and above, backslash escapes metacharacters inside and outside character classes
  7. 21.6 Testing Regular Expressions¶. Since JMeter 2.4, the listener View Results Tree include a RegExp Tester to test regular expressions directly on sampler response data.. There is a Website to test Java Regular expressions.. Another approach is to use a simple test plan to test the regular expressions. The Java Request sampler can be used to generate a sample, or the HTTP Sampler can be used.

Escape sequences are special characters in regular expressions preceded by a backslash (). You typically use escape sequences to represent special characters within a regular expression. For example, the escape sequence \t represents a tab character within the regular expression, and the \d escape sequence specifies any digit, as [0-9] does As backslashes are also used to escape special characters in PHP strings, we must use a double backslash for each single backslash that we with to have in the regular expression.. I understand. LEX regular expressions. LEX REGULAR EXPRESSIONS. A LEX regular expression is a word made of text characters (letters of the alphabet, digits,) operators : \ { } [ ] ^ $ < > ? . * + | / Moreover An operator can be used as a text character if it preceeded with the escape operator (backslash) Browse other questions tagged regular-expression or ask your own question. The Overflow Blog Celebrating the Stack Exchange sites that turned 10 years old. Podcast 367: Building a better developer Why does backslash-escaping a CJK character cause a very-magic regex match to fail? 3 Name \ (Backslash) — Escapes a metacharacter Synopsis Use the backslash (\) to treat as normal a character that would otherwise have a special meaning. For example, to - Selection from Oracle Regular Expressions Pocket Reference [Book

Regular Expression (Regex) Tutoria

  1. The backslash character (\) is the escaping character.It can be used to denote an escaped character, a string, literal, or one of the set of supported special characters. Use a double backslash (\\) to denote an escaped string literal.For more information, see Escaping Strings in Transformations. Supported Special RegEx Characters. The table below identifies the special characters that are.
  2. Regular expressions use the backslash character ('\') to indicate special forms or to allow special characters to be used without invoking their special meaning. This collides with Python's usage of the same character for the same purpose in string literals; for example, to match a literal backslash, one might have to write '\\\\' as the pattern string, because the regular expression must be.
  3. To understand extended regular expressions, we need to compare them to basic regular expressions (BRE). These expressions are also referred to as POSIX (Portable Operating System Interface for Unix) basic regular expressions. The difference between ERE and BRE is what happens when you add a backslash in front of a character within an expression
  4. Regular expressions can be used to find regular patterns in strings and in Julia regular expressions are themselves input as strings which are parsed into a state machine that can be used to efficiently search for patterns in strings. A backslash always escapes the character that follows it
  5. group are Multilingual Regular Expression Syntax (Pattern) that normally capture the match during the parsing. You can then (extract|reference) the match content. Groups are inside parentheses. Regexp - Look-around group (Assertion) - ( Lookahead | Lookbehind )groups Articles Related Syntax Every group must begin with an open bracket and end with a close bracket
  6. e if some other string, called the target, has (or doesn't have) the characteristics specified by the pattern
  7. Regular expressions are patterns used to match character combinations in strings. In JavaScript, regular expressions are also objects. These patterns are used with the exec() and test() methods of RegExp, and with the match(), matchAll(), replace(), replaceAll(), search(), and split() methods of String. This chapter describes JavaScript regular expressions

Forming Regular Expressions. Scala inherits its regular expression syntax from Java, which in turn inherits most of the features of Perl. Here are just some examples that should be enough as refreshers −. Following is the table listing down all the regular expression Meta character syntax available in Java Regular expression, specified as a character vector, a cell array of character vectors, or a string array. Each expression can contain characters, metacharacters, operators, tokens, and flags that specify patterns to match in str. The following tables describe the elements of regular expressions. Metacharacter Escape Character in Regular Expressionhttps://www.LearnCodeOnline.infb: https://www.facebook.com/HiteshChoudharyPagehomepage: http://www.hiteshChoudhary.comD.. Regular expression when used correctly can greatly enhance the program's ability to find and detect keywords and key phrases. Another benefit for users is the ability to condense a large number of key elements into a string, without the need to make a unique separate entry for each target website or application Regular expression is a language that does not have a NOT operator but it has some negative construct Articles Related Construct Negative Class ^ will negate the Regexp - Character Class, ie capture until not this characters Example

regular expression - grep: Trailing backslash - Unix & Linux Stack Exchang

  1. Keeping this in consideration, is a special character in regex? All other characters should not be escaped with a backslash. That is because the backslash is also a special character.The backslash in combination with a literal character can create a regex token with a special meaning. Escaping a single metacharacter with a backslash works in all regular expression flavors
  2. In JavaScript, Regular Expressions also known as regex are patterns used to match, replace, compare character combinations in strings. When we search for some specific data in a text, we can use a regular expression to be used as a search pattern to describe what you are searching for
  3. Regular expression substitution. pedamase (Sekhar Pedamallu) July 17, 2021, 12:32pm #1. Hi, Regualar expression substitution does not work for below code. Want to replace whole word 'mall' that occurs at the starting of the line with '1234'. Any help
  4. In particular, if you want to match a backslash, you write \\. Note: Single and double quoted PHP strings have special meaning of backslash. Thus if \ has to be matched with a regular expression \\, then \\\\ or '\\\\' must be used in PHP code
  5. In particular, if you want a regular expression that matches a single backslash character, you need to quote it in the argument to regexp (according to the last item of the list above) by adding a second backslash
  6. Brief Background. A regular expression consists of a character string where some characters are given special meaning with regard to pattern matching. Regular expressions have been in use from the early days of computing, and provide a powerful and efficient way to parse, interpret and search and replace text within an application
A Visual Guide to Regular Expression

A regular expression is a sequence of logically combined characters and meta characters (characters with special meaning) that, according to parsing rules in the regexp engine, describes text which matches a certain pattern. I will assume you are familiar with both PowerShell and regular expressions and want to know how to use the latter in PowerShell According to Python docs, perhaps the most important metacharacter in regular expressions is the backslash, \. As in Python string literals, the backslash can be followed by various characters to indicate various special sequences. It's also used to escape all the metacharacters so you can still match them in patterns; for example, if you need to match a [ or \, you can precede them with a. The use of backslash to design a generic character class of characters (called also shorthand) Regexp - Character Class. Character - Whitespace. Sh - String Variable. Regexp - Backslash. Regexp - Word Characters. Regular Expression - Line (Beginning and End regex - Backslash regular expression JavaScript. I wanted to build a JS function concatting a list of arguments to a valid path (since I could not be sure whether a part of the path is given with or without slashes) This is the function

Regular expression characters and usage options. Relevant for: GUI tests and components and API testing. This section describes some of the more common options that can be used to create regular expressions: Backslash Character ( \ ) A backslash (\) can serve two purposes. It can be used in conjunction with a special character to indicate that. A backslash before a wildcard character tells the Code Editor to treat that character literally, not as a wildcard. For example, \^ matches ^ and does not look for the start of a line. If you enable BRIEF regular expressions , you can use the BRIEF regular expression symbols in your regular expressions, instead of the symbols in the table above Regular expressions are a major programming topic, far beyond what is described here. In C scripts, to pass a regular expression that contains a backslash, precede the RE backslash with another backslash. For example, to pass the regular expression, \*, meaning to find a literal asterisk, pass \\*

In a regular expression that is defined by using static text, characters that are to be interpreted literally rather than as metacharacters can be escaped by preceding them with a backslash symbol (\) as well as by calling the Escape method Matches a backslash. Metacharacters. Matches or does not match depending on the position in the string. Character Escapes; Regular Expression Description ^ Matches the matched item at the beginning of the string. For example, the pattern ^\d{2} matches 12 in 12-34. $ Matches the. R has a quirk when entering regular expressions: most backslashes need to be preceded by an additional backslash. \ becomes \\ and \n becomes \\n. There are often multiple ways of constructing a given regular expression. Every programming language has its own quirks. Here, I've attempted to privilege consistency

Java regular expression syntax uses the backslash character as escape character, just like Java Strings do. This gives a little challenge when writing a regular expression in a Java string. Look at this regular expression example: String regex = \\.; Notice that the regular expression String contains two backslashes after each other, and then a Regular expressions use special characters (metacharacters) to denote which characters to match in the source content. You must be careful when adding words/phrases to this list so that they aren't interpreted differently than you expect them to be. The special characters are: backslash \ caret ^ dollar sign $ period or dot RE : ConstraintLayout buttons going off screen By Jcmarimarissa - on July 17, 2020 . Remove the hardcoded top margin of the EditDate, and center it vertically in parent with app:layout_constraintBottom_toBottomOf=parent Also add app:layout_constraintBottom_toBottomOf=parent to..

Regular Expressions Tutorial - Anchor Characters: Caret (^

Regular Expressions. TestStand supports a limited subset of regular expression syntax that other applications or operating systems support. A regular expression in TestStand can contain any of the following tokens: Match 1 character. Match 0 or more occurrences of the preceding character or {expression}. Match 1 or more occurrences of the. The backslash (\) signals to a regular expression that the following character, if it has a special regular expression meaning, should be interpreted literally, not in its special regex sense. So . by itself means any single character, while \ Regular expressions are constructed analogously to arithmetic expressions by using various operators to combine smaller expressions. Any metacharacter with special meaning may be quoted by preceding it with a backslash. 4.1.2. Regular expression metacharacters. A regular expression may be followed by one of several repetition.

Javascript regex generator — scriptular is a javascript

Table of Contents. Fundamentals; Options (case sensitive) Commonly Used Symbols and Syntax; Fundamentals. Match anywhere: By default, a regular expression matches a substring anywhere inside the string to be searched. For example, the regular expression abc matches abc 123, 123 abc, and 123 abc xyz. To require the match to occur only at the beginning or end, use an anchor In this example \d is the regular expression; the extra backslash is required for the code to compile. The test harness reads the expressions directly from the Console, however, so the extra backslash is unnecessary. The following examples demonstrate the use of predefined character classes How to Use Regular Expression in UFT/QTP. Regular Expression is used in Object Identification in object repository as well as descriptive programming. Consider a website that displays month and date. As the text property is all properties except object class are dynamic and nature and change every other day and month, it would become a challenging task if you have to check whether this web.

Regex Tutorial - Literal Characters and Special Character

Introduction. In this post, we will learn about using regular expressions in R. While it is aimed at absolute beginners, we hope experienced users will find it useful as well. The post is broadly divided into 3 sections. In the first section, we will introduce the pattern matching functions such as grep, grepl etc. in base R as we will be using them in the rest of the post Using Regular Expressions in Custom Sites. Select URLs are defined as Regular Expression only if the application or site URL is entered as a regular expression using the correct syntax.. The meaning of the asterisk ( * ) depends on its use. In regular expressions, the asterisk is a metacharacter for zero or more instances of the preceding character SPL and regular expressions. Splunk Search Processing Language (SPL) regular expressions are PCRE (Perl Compatible Regular Expressions). You can use regular expressions with the rex and regex commands. You can also use regular expressions with evaluation functions such as match and replace.. Here are a few things that you should know about using regular expressions in Splunk searches Basic regular expressions use a backslash prior to a question mark when used to mean zero or one of the previous character or group. Extended regular expressions do not. This operator is described in Wildcards and Repetition Operators. Perl regular expressions are equivalent to extended regular expressions with a few additional features Regular expressions in XSD 1.0 and 1.1 C. M. Sperberg-McQueen Begun 25-27 March 2008. Last revised &date.last.touched; (Minor encoding fixes 9 December 2009) This note describes some issues relating to the regular-expression language defined by XSD 1.0 and 1.1. The grammar implies that backslash, hyphen,.

Regular Expressions as used in R Description. This help page documents the regular expression patterns supported by grep and related functions grepl, regexpr, gregexpr, sub and gsub, as well as by strsplit and optionally by agrep and agrepl. Details. A 'regular expression' is a pattern that describes a set of strings. Two types of regular expressions are used in R, extended regular. About the Regular Expression Protection policy. Apigee Edge enables you to configure regular expressions that can be evaluated against API traffic at runtime to identify common content-level threats that follow certain patterns.. A regular expression, or regex for short, is a set of strings that specify a pattern in a string. . Regular expressions enable content to be programmatically. A regular expression is a string of characters that contains a pattern to find the string or strings you are looking for. In its simplest form, a regular expression is just a word or phrase to search for in the source string. Regular expressions include metacharacters which are special characters that add a great deal of flexibility and convenience to the search The backslash sequences \n and \x20 have no meaning to Perl's regular expression engine, which, in fact, never sees them. Those sequences are interpreted by Perl itself. By the time the string gets to Perl's regular expression engine, \n and \x20 have been replaced by the appropriate byte codes BRE Exceptions. While ERE (extended regular expressions) mirrors the typical, Perl-style syntax, BRE (basic regular expressions) has significant differences when it comes to escaping: There is different shorthand syntax. All of the \d, \s, \w and so on is gone. Instead, it has its own syntax (which POSIX confusingly calls character classes), like [:digit:]

Backslash in string literals Mastering Python Regular Expression

  1. First of all, note that the regular expression r'wo\w+' is written as a raw string, as indicated by the r'...' string prefix. That is because regular expressions, as you are aware by now, use the backslash \ as their own special escape character, and without 'r' the backslash gets interpreted as *Python's* special escape character. Basically, on Python's string object level, that \ in \w.
  2. Match the <regular_expression> as many times as possible and substitute the <replacement_expression> for the match in the output. All <input> arguments are concatenated before matching.. The <replacement_expression> may refer to parenthesis-delimited subexpressions of the match using \1, \2 \9.Note that two backslashes (\\1) are required in CMake code to get a backslash through argument.
  3. In JavaScript, Regular Expressions also known as regex are patterns used to match, replace, compare character combinations in strings. When we search for some specific data in a text, we can use a regular expression to be used as a search pattern to describe what you are searching for
  4. Text Analytics Toolbox provides functions for common text preprocessing steps
  5. perlrebackslash - Perl Regular Expression Backslash Sequences and Escapes - Perldoc
  6. How to Match A Backslash with preg_match() in PH
  7. Regular expression replace with backslash - Custom IC SKILL - Cadence Technology
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