Perl Cheat Sheet



Perl Reference Card Cheat Sheet by Nikolay Mishin (mishin) via cheatography.com/1008/cs/399/. Perl, short version Cheat Sheet. Long version construction and short analog in Perl. Computer Programming Languages. Computer Coding. Computer Technology. Computer Science. C Programming Learning. Html Programming Language.

Finally Affinity Designer has released its version of the ipad app, and it is EPIC! And as 7 th season studios is the premier instructor on multiple platforms in the Affinity Space, it is only logical that we present THE BIGGEST, MOST COMPREHENSIVE Affinity Designer course for the ipad out there in the market today Affinity Designer on the ipad. Affinity Designer for iPad for $19.99. Terms & Conditions; 0 0. Affinity Designer Workbook for $49.99. Terms & Conditions; 0 0. Christmas Sale - 20% off everything From Affinity: 01-02-19: Discover your favorite coupon through 23 live and hot Affinity coupon codes and deals. Shop at affinity.serif.com and get. Optimized for the latest tech on Mac, Windows and iPad, Affinity Designer is setting the new industry standard in the world of design. Best in class for creating concept art, print projects, logos, icons, UI designs, mock-ups and more, it’s already the top choice of thousands of professional illustrators, web designers, game developers. Affinity designer ipad save to cloud.

The tables below are a reference to basic regex. While reading the rest of the site, when in doubt, you can always come back and look here. (It you want a bookmark, here's a direct link to the regex reference tables). I encourage you to print the tables so you have a cheat sheet on your desk for quick reference.
The tables are not exhaustive, for two reasons. First, every regex flavor is different, and I didn't want to crowd the page with overly exotic syntax. For a full reference to the particular regex flavors you'll be using, it's always best to go straight to the source. In fact, for some regex engines (such as Perl, PCRE, Java and .NET) you may want to check once a year, as their creators often introduce new features.
The other reason the tables are not exhaustive is that I wanted them to serve as a quick introduction to regex. If you are a complete beginner, you should get a firm grasp of basic regex syntax just by reading the examples in the tables. I tried to introduce features in a logical order and to keep out oddities that I've never seen in actual use, such as the 'bell character'. With these tables as a jumping board, you will be able to advance to mastery by exploring the other pages on the site.

How to use the tables

The tables are meant to serve as an accelerated regex course, and they are meant to be read slowly, one line at a time. On each line, in the leftmost column, you will find a new element of regex syntax. The next column, 'Legend', explains what the element means (or encodes) in the regex syntax. The next two columns work hand in hand: the 'Example' column gives a valid regular expression that uses the element, and the 'Sample Match' column presents a text string that could be matched by the regular expression.
You can read the tables online, of course, but if you suffer from even the mildest case of online-ADD (attention deficit disorder), like most of us… Well then, I highly recommend you print them out. You'll be able to study them slowly, and to use them as a cheat sheet later, when you are reading the rest of the site or experimenting with your own regular expressions.
Enjoy!
If you overdose, make sure not to miss the next page, which comes back down to Earth and talks about some really cool stuff: The 1001 ways to use Regex.

Regex Accelerated Course and Cheat Sheet

For easy navigation, here are some jumping points to various sections of the page:
✽ Characters
✽ Quantifiers
✽ More Characters
✽ Logic
✽ More White-Space
✽ More Quantifiers
✽ Character Classes
✽ Anchors and Boundaries
✽ POSIX Classes
✽ Inline Modifiers
✽ Lookarounds
✽ Character Class Operations
✽ Other Syntax
(direct link)

Characters

CharacterLegendExampleSample Match
dMost engines: one digit
from 0 to 9
file_ddfile_25
d.NET, Python 3: one Unicode digit in any scriptfile_ddfile_9੩
wMost engines: 'word character': ASCII letter, digit or underscorew-wwwA-b_1
w.Python 3: 'word character': Unicode letter, ideogram, digit, or underscorew-www字-ま_۳
w.NET: 'word character': Unicode letter, ideogram, digit, or connectorw-www字-ま‿۳
sMost engines: 'whitespace character': space, tab, newline, carriage return, vertical tabasbsca b
c
s.NET, Python 3, JavaScript: 'whitespace character': any Unicode separatorasbsca b
c
DOne character that is not a digit as defined by your engine's dDDDABC
WOne character that is not a word character as defined by your engine's wWWWWW*-+=)
SOne character that is not a whitespace character as defined by your engine's sSSSSYoyo

(direct link)Cheat

Quantifiers

QuantifierLegendExampleSample Match
+One or moreVersion w-w+Version A-b1_1
{3}Exactly three timesD{3}ABC
{2,4}Two to four timesd{2,4}156
{3,}Three or more timesw{3,}regex_tutorial
*Zero or more timesA*B*C*AAACC
?Once or noneplurals?plural

(direct link)

More Characters

CharacterLegendExampleSample Match
.Any character except line breaka.cabc
.Any character except line break.*whatever, man.
.A period (special character: needs to be escaped by a )a.ca.c
Escapes a special character.*+? $^/.*+? $^/
Escapes a special character[{()}][{()}]

(direct link)

Logic

LogicLegendExampleSample Match
| Alternation / OR operand22|3333
( … )Capturing groupA(nt|pple)Apple (captures 'pple')
1Contents of Group 1r(w)g1xregex
2Contents of Group 2(dd)+(dd)=2+112+65=65+12
(?: … )Non-capturing groupA(?:nt|pple)Apple

(direct link)

More White-Space

CharacterLegendExampleSample Match
tTabTtw{2}T ab
rCarriage return charactersee below
nLine feed charactersee below
rnLine separator on WindowsABrnCDAB
CD
NPerl, PCRE (C, PHP, R…): one character that is not a line breakN+ABC
hPerl, PCRE (C, PHP, R…), Java: one horizontal whitespace character: tab or Unicode space separator
HOne character that is not a horizontal whitespace
v.NET, JavaScript, Python, Ruby: vertical tab
vPerl, PCRE (C, PHP, R…), Java: one vertical whitespace character: line feed, carriage return, vertical tab, form feed, paragraph or line separator
VPerl, PCRE (C, PHP, R…), Java: any character that is not a vertical whitespace
RPerl, PCRE (C, PHP, R…), Java: one line break (carriage return + line feed pair, and all the characters matched by v)

(direct link)

More Quantifiers

QuantifierLegendExampleSample Match
+The + (one or more) is 'greedy'd+12345
?Makes quantifiers 'lazy'd+?1 in 12345
*The * (zero or more) is 'greedy'A*AAA
?Makes quantifiers 'lazy'A*?empty in AAA
{2,4}Two to four times, 'greedy'w{2,4}abcd
?Makes quantifiers 'lazy'w{2,4}?ab in abcd

(direct link)

Character Classes

CharacterLegendExampleSample Match
[ … ]One of the characters in the brackets[AEIOU]One uppercase vowel
[ … ]One of the characters in the bracketsT[ao]pTap or Top
-Range indicator[a-z]One lowercase letter
[x-y]One of the characters in the range from x to y[A-Z]+GREAT
[ … ]One of the characters in the brackets[AB1-5w-z]One of either: A,B,1,2,3,4,5,w,x,y,z
[x-y]One of the characters in the range from x to y[ -~]+Characters in the printable section of the ASCII table.
[^x]One character that is not x[^a-z]{3}A1!
[^x-y]One of the characters not in the range from x to y[^ -~]+Characters that are not in the printable section of the ASCII table.
[dD]One character that is a digit or a non-digit[dD]+Any characters, inc-
luding new lines, which the regular dot doesn't match
[x41]Matches the character at hexadecimal position 41 in the ASCII table, i.e. A[x41-x45]{3}ABE

(direct link)

Anchors and Boundaries

Perl For Dummies

AnchorLegendExampleSample Match
^Start of string or start of line depending on multiline mode. (But when [^inside brackets], it means 'not')^abc .*abc (line start)
$End of string or end of line depending on multiline mode. Many engine-dependent subtleties..*? the end$this is the end
ABeginning of string
(all major engines except JS)
Aabc[dD]*abc (string..
..start)
zVery end of the string
Not available in Python and JS
the endzthis is..n..the end
ZEnd of string or (except Python) before final line break
Not available in JS
the endZthis is..n..the endn
GBeginning of String or End of Previous Match
.NET, Java, PCRE (C, PHP, R…), Perl, Ruby
bWord boundary
Most engines: position where one side only is an ASCII letter, digit or underscore
Bob.*bcatbBob ate the cat
bWord boundary
.NET, Java, Python 3, Ruby: position where one side only is a Unicode letter, digit or underscore
Bob.*bкошкаbBob ate the кошка
BNot a word boundaryc.*BcatB.*copycats

(direct link)

POSIX Classes

CharacterLegendExampleSample Match
[:alpha:]PCRE (C, PHP, R…): ASCII letters A-Z and a-z[8[:alpha:]]+WellDone88
[:alpha:]Ruby 2: Unicode letter or ideogram[[:alpha:]d]+кошка99
[:alnum:]PCRE (C, PHP, R…): ASCII digits and letters A-Z and a-z[[:alnum:]]{10}ABCDE12345
[:alnum:]Ruby 2: Unicode digit, letter or ideogram[[:alnum:]]{10}кошка90210
[:punct:]PCRE (C, PHP, R…): ASCII punctuation mark[[:punct:]]+?!.,:;
[:punct:]Ruby: Unicode punctuation mark[[:punct:]]+‽,:〽⁆

(direct link)

Inline Modifiers

None of these are supported in JavaScript. In Ruby, beware of (?s) and (?m).

Perl Regular Expression Cheat Sheet


ModifierLegendExampleSample Match
(?i)Case-insensitive mode
(except JavaScript)
(?i)MondaymonDAY
(?s)DOTALL mode (except JS and Ruby). The dot (.) matches new line characters (rn). Also known as 'single-line mode' because the dot treats the entire input as a single line(?s)From A.*to ZFrom A
to Z
(?m)Multiline mode
(except Ruby and JS) ^ and $ match at the beginning and end of every line
(?m)1rn^2$rn^3$1
2
3
(?m)In Ruby: the same as (?s) in other engines, i.e. DOTALL mode, i.e. dot matches line breaks(?m)From A.*to ZFrom A
to Z
(?x)Free-Spacing Mode mode
(except JavaScript). Also known as comment mode or whitespace mode
(?x) # this is a
# comment
abc # write on multiple
# lines
[ ]d # spaces must be
# in brackets
abc d
(?n).NET, PCRE 10.30+: named capture onlyTurns all (parentheses) into non-capture groups. To capture, use named groups.
(?d)Java: Unix linebreaks onlyThe dot and the ^ and $ anchors are only affected by n
(?^)PCRE 10.32+: unset modifiersUnsets ismnx modifiers

(direct link)

Lookarounds

LookaroundLegendExampleSample Match
(?=…)Positive lookahead(?=d{10})d{5}01234 in 0123456789
(?<=…)Positive lookbehind(?<=d)catcat in 1cat
(?!…)Negative lookahead(?!theatre)thew+theme
(?<!…)Negative lookbehindw{3}(?<!mon)sterMunster

(direct link)

Character Class Operations

Class OperationLegendExampleSample Match
[…-[…]].NET: character class subtraction. One character that is in those on the left, but not in the subtracted class.[a-z-[aeiou]]Any lowercase consonant
[…-[…]].NET: character class subtraction.[p{IsArabic}-[D]]An Arabic character that is not a non-digit, i.e., an Arabic digit
[…&&[…]]Java, Ruby 2+: character class intersection. One character that is both in those on the left and in the && class.[S&&[D]]An non-whitespace character that is a non-digit.
[…&&[…]]Java, Ruby 2+: character class intersection.[S&&[D]&&[^a-zA-Z]]An non-whitespace character that a non-digit and not a letter.
[…&&[^…]]Java, Ruby 2+: character class subtraction is obtained by intersecting a class with a negated class[a-z&&[^aeiou]]An English lowercase letter that is not a vowel.
[…&&[^…]]Java, Ruby 2+: character class subtraction[p{InArabic}&&[^p{L}p{N}]]An Arabic character that is not a letter or a number

(direct link)

Other Syntax

SyntaxLegendExampleSample Match
KKeep Out
Perl, PCRE (C, PHP, R…), Python's alternate regex engine, Ruby 2+: drop everything that was matched so far from the overall match to be returned
prefixKd+12
Q…EPerl, PCRE (C, PHP, R…), Java: treat anything between the delimiters as a literal string. Useful to escape metacharacters.Q(C++ ?)E(C++ ?)

Don't Miss The Regex Style Guide
and The Best Regex Trick Ever!!!

The 1001 ways to use Regex

1-10 of 17 Threads
Subject: Very thoughtful and useful cheat sheet

Unlike lots of other cheat sheets or regex web sites, I was able (without much persistent regex knowledge) to apply the rules and to solve my problem. THANK YOU :)
Subject: Thanks a lot

Thanks a lot for the quick guide. It's really helpful.
Subject: Very useful site

Thank you soooooo much for this site. I'm using python regex for natural language processing in sentiment analysis and this helped me a lot.
Perl
Subject: Thank you! Excellent resource for any student

Thank you so much for this incredible cheatsheet! It is facilitating a lot my regex learning! God bless you and your passion!
Subject: Thank you for doing such a geat work.

I am now learning regex and for finding such a well organized site is a blessing! You are a good soul! Thank you for everything and stay inspired!
Subject: Simple = perfect

Subject: Congratulations

Well done, very useful page. Thank you for your effort. T
Subject: Thank you very much

Hi Rex,
Thankyou very much for compiling these. I am new to text analytics and is struggling a lot with regex. This is helping me a lot pick up. Great work
Subject: Nice summary

Nice summary of regex. I was trying to remember how to group and I found the example above. Thanks.
Subject: Best Regex site ever

This is the best regex site ever on the internet. Regular Expressions are like any other language, they require time and effort to learn. RexEgg makes it an easy journey. Great work Author. Kudos to you.

Perl Debugger Cheat Sheet



This document presents a tabular summary of the regular expression (regexp) syntax in Perl, then illustrates it with a collection of annotated examples.

Metacharacters

charmeaning
^beginning of string
$end of string
.any character except newline
*match 0 or more times
+match 1 or more times
?match 0 or 1 times; or: shortest match
|alternative
grouping; “storing”
set of characters
repetition modifier
quote or special

To present a metacharacter as a data character standing for itself, precede it with (e.g. . matches the full stop character . only).

In the table above, the characters themselves, in the first column, are links to descriptions of characters in my The ISO Latin 1 character repertoire - a description with usage notes. Note that the physical appearance (glyph) of a character may vary from one device or program or font to another.

Repetition

a*zero or more a’s
a+one or more a’s
a?zero or one a’s (i.e., optional a)
a{m}exactly ma’s
a{m,}at least ma’s
a{m,n}at least m but at most n a’s
repetition?same as repetition but the shortest match is taken

Read the notation a’s as “occurrences of strings, each of which matches the pattern a”. Read repetition as any of the repetition expressions listed above it. Shortest match means that the shortest string matching the pattern is taken. The default is “greedy matching”, which finds the longest match. The repetition? construct was introduced in Perl version 5.

Special notations with

Single characters
ttab
nnewline
rreturn (CR)
xhhcharacter with hex. code hh
“Zero-width assertions”
b“word” boundary
Bnot a “word” boundary
Matching
wmatches any single character classified as a “word” character (alphanumeric or “_”)
Wmatches any non-“word” character
smatches any whitespace character (space, tab, newline)
Smatches any non-whitespace character
dmatches any digit character, equiv. to [0-9]
Dmatches any non-digit character

Perl Regular Expressions Cheat Sheet

Character sets: specialities inside [..]

Perl Cheat Sheet Of Functions

Perl debugger cheat sheet

Cisco anyconnect vpn client download windows 10 64 bit free. Different meanings apply inside a character set (“character class”) denoted by [..] so that, instead of the normal rules given here, the following apply:

[characters]matches any of the characters in the sequence
[x-y]matches any of the characters from x to y (inclusively) in the ASCII code
[-]matches the hyphen character “-
[n]matches the newline; other single character denotations with apply normally, too
[^something]matches any character except those that [something] denotes; that is, immediately after the leading “[”, the circumflex “^” means “not” applied to all of the rest

Examples

expressionmatches..
abcabc (that exact character sequence, but anywhere in the string)
^abcabc at the beginning of the string
abc$abc at the end of the string
a|beither of a and b
^abc|abc$the string abc at the beginning or at the end of the string
ab{2,4}can a followed by two, three or four b’s followed by a c
ab{2,}can a followed by at least two b’s followed by a c
ab*can a followed by any number (zero or more) of b’s followed by a c
ab+can a followed by one or more b’s followed by a c
ab?can a followed by an optional b followed by a c; that is, either abc or ac
a.can a followed by any single character (not newline) followed by a c
a.ca.c exactly
[abc]any one of a, b and c
[Aa]bceither of Abc and abc
[abc]+any (nonempty) string of a’s, b’s and c’s (such as a, abba, acbabcacaa)
[^abc]+any (nonempty) string which does not contain any of a, b and c (such as defg)
ddany two decimal digits, such as 42; same as d{2}
w+a “word”: a nonempty sequence of alphanumeric characters and low lines (underscores), such as foo and 12bar8 and foo_1
100s*mkthe strings 100 and mk optionally separated by any amount of white space (spaces, tabs, newlines)
abcbabc when followed by a word boundary (e.g. in abc! but not in abcd)
perlBperl when not followed by a word boundary (e.g. in perlert but not in perl stuff)

Examples of simple use in Perl statements

Perl Injection Cheat Sheet

These examples use very simple regexps only. The intent is just to show contexts where regexps might be used, as well as the effect of some “flags” to matching and replacements. Note in particular that matching is by default case-sensitive (Abc does not match abc unless specified otherwise).

s/foo/bar/;
replaces the first occurrence of the exact character sequence foo in the “current string” (in special variable $_) by the character sequence bar; for example, foolish bigfoot would become barlish bigfoot

Xerox printers driver download for windows. s/foo/bar/g;
replaces any occurrence of the exact character sequence foo in the “current string” by the character sequence bar; for example, foolish bigfoot would become barlish bigbart

s/foo/bar/gi;
replaces any occurrence of foocase-insensitively in the “current string” by the character sequence bar (e.g. Foo and FOO get replaced by bar too)

if(m/foo/)..
tests whether the current string contains the string foo

Date of creation: 2000-01-28. Last revision: 2007-04-16. Last modification: 2007-05-28.

Finnish translation – suomennos: Säännölliset lausekkeet Perlissä.

The inspiration for my writing this document was Appendix : A Summary of Perl Regular Expressions in Pankaj Kamthan’s CGI Security : Better Safe than Sorry, and my own repeated failures to memorize the syntax.

This page belongs to section Programming of the free information site IT and communication by Jukka “Yucca” Korpela.