Regular Expressions 101

Save & Share

Flavor

  • PCRE2 (PHP >=7.3)
  • PCRE (PHP <7.3)
  • ECMAScript (JavaScript)
  • Python
  • Golang
  • Java 8
  • .NET 7.0 (C#)
  • Rust
  • Regex Flavor Guide

Function

  • Match
  • Substitution
  • List
  • Unit Tests

Tools

Sponsors
There are currently no sponsors. Become a sponsor today!
An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?m)\b(?<=\w)\s{20}" Local $sString = "Ateles_geoffroyi GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Ateles_hybridus GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Ateles_fusciceps GATGAGTGTGGCAAGGCCCAAGCGGAAGTGC??????????" & @CRLF & _ "Ateles_chamek GATGAGTGTGGCAAGGCCCA?????????????????????" & @CRLF & _ "Ateles_paniscus ?????????????????????????????????????????" & @CRLF & _ "Brachyteles_arachnoides GATGAGTGTGGCAAGGCCCAAGCGGAAGT????????????" & @CRLF & _ "Brachyteles_hypoxanthus GATGAGTGTGGCAAG??????????????????????????" & @CRLF & _ "Lagothrix_cana GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Lagothrix_lagotricha GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Alouatta_belzebul ?????????????????????????????????????????" & @CRLF & _ "Alouatta_caraya ?????????????????????????????????????????" & @CRLF & _ "Alouatta_sara GATGAATGTGGCAAGGCCCAAGCAGAAGTGCCG--GTTGCT" & @CRLF & _ "Alouatta_palliata GATGAATGTGGCAAGGCCCAAGCAGAAGTGCCG--GTTGCT" & @CRLF & _ "Callicebus_brunneus ?????????????????????????????????????????" & @CRLF & _ "Callicebus_moloch GATGAGTGTGGCAAGGCCCAAGCAGAAGTGCCG--G?????" & @CRLF & _ "Callicebus_cupreus GATGAGTGTGGCAAGGCCCAAGCAGAAGTGCCG--GTTGCT" & @CRLF & _ "Callicebus_caligatus GATGAGTGTGGCAAGGCCCAAGCAGAAGTGCCG--GTTGCT" & @CRLF & _ "Callicebus_donacophilus GATGAGTGTGGCAAGGCCCAAGCAGAAGTGCCG--GTTGCT" & @CRLF & _ "Callicebus_coimbrai GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Callicebus_personatus GATGAGTGTGGCAAGGCCCAAGCGGAA??????????????" & @CRLF & _ "Callicebus_nigrifrons GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Cacajao_melanocephalus GATGAGTGTGGCAAAGCCCA?????????????????????" & @CRLF & _ "Cacajao_calvus GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Chiropotes_israelita GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Chiropotes_satanas_chiro ?????????????????????????????????????????" & @CRLF & _ "Pithecia_irrorata GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--G?????" & @CRLF & _ "Pithecia_pithecia GATGAGTGTGGCAAGGCCCAAGCGGAAGTGCCG--GTTGCT" & @CRLF & _ "Tarsius_bancanus ?????????????????????????????????????????" & @CRLF & _ "Tarsius_syrichta ?????????????????????????????????????????" & @CRLF & _ "Lepilemur_ankaranensis AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Lepilemur_septentrionali AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Lepilemur_dorsalis AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Lepilemur_ruficaudatus AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Lepilemur_jamesi AACGAGTGTGGCAAGGCCCAGG???????????????????" & @CRLF & _ "Microcebus_murinus_subsp AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Microcebus_murinus_subsp ?????????????????????????????????????????" & @CRLF & _ "Mirza_zaza AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Cheirogaleus_medius ?????????????????????????????????????????" & @CRLF & _ "Propithecus_verreauxi_co ?????????????????????????????????????????" & @CRLF & _ "Propithecus_verreauxi AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Propithecus_tattersalli AACGAGTGTGGCAAGGCCCAGGCTGAAGTTCCG--GTTGCT" & @CRLF & _ "Propithecus_diadema AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Propithecus_edwardsi AACGAGTGTGGCAAGGCCCAGGCG?????????????????" & @CRLF & _ "Avahi_laniger AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_rufus AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_collaris AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_fulvus AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_albifrons AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_sanfordi AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_mongoz AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_macaco AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_macaco_flavifron AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_coronatus AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Eulemur_rubriventer AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Hapalemur_occidentalis AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Hapalemur_griseus AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Lemur_catta AACGAGTGTGGCAAGGCCCAGGCGGAAGTTCCG--GTTGCT" & @CRLF & _ "Varecia_variegata_varieg AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Varecia_variegata_rubra AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Daubentonia_madagascarie ?????????????????????????????????????????" & @CRLF & _ "Nycticebus_bengalensis AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Nycticebus_coucang AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Nycticebus_pygmaeus AACGAGTATGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Loris_tardigradus AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Arctocebus_calabarensis AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Perodicticus_potto AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Otolemur_garnetti AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Otolemur_crassicaudatus AACGAGTGTGGCAAGGCCCAGGCAGAAGTTCCG--GTTGCT" & @CRLF & _ "Galago_moholi ?????????????????????????????????????????" & @CRLF & _ "Galago_senegalensis ?????????????????????????????????????????" & @CRLF & _ "Galago_thomasi AACGAGTGTGGCAAGGCCCAGGCG?????????????????" & @CRLF & _ "Galeopterus_variegatus GATGAGTGTGGCAAGGCCCAAGCAGAAGTTCCG--G?????" & @CRLF & _ "Cynocephalus_volans GATGAGTGTGGCAAGGCCCAAGCAGAAGTCCCG--GTTGCT" & @CRLF & _ "Tupaia_glis ?????????????????????????????????????????" & @CRLF & _ "Tupaia_minor ?????????????????????????????????????????" & @CRLF & _ "rabbit_rabbit_rabbit ?????????????????????????????????????????" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm