Regular Expressions 101

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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

/
/
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 $sRegex = "(?m)^((\s+|)(\/\/|#)|$)" Local $sString = "##################################################################" & @CRLF & _ "#### /etc/apt/apt.conf.d/50unattended-upgrades ###" & @CRLF & _ "// Automatically upgrade packages from these (origin:archive) pairs" & @CRLF & _ "//" & @CRLF & _ "// Note that in Ubuntu security updates may pull in new dependencies" & @CRLF & _ "// from non-security sources (e.g. chromium). By allowing the release" & @CRLF & _ "// pocket these get automatically pulled in." & @CRLF & _ "Unattended-Upgrade::Allowed-Origins {" & @CRLF & _ " "${distro_id}:${distro_codename}";" & @CRLF & _ " "${distro_id}:${distro_codename}-security";" & @CRLF & _ " // Extended Security Maintenance; doesn't necessarily exist for" & @CRLF & _ " // every release and this system may not have it installed, but if" & @CRLF & _ " // available, the policy for updates is such that unattended-upgrades" & @CRLF & _ " // should also install from here by default." & @CRLF & _ " "${distro_id}ESMApps:${distro_codename}-apps-security";" & @CRLF & _ " "${distro_id}ESM:${distro_codename}-infra-security";" & @CRLF & _ "// "${distro_id}:${distro_codename}-updates";" & @CRLF & _ "// "${distro_id}:${distro_codename}-proposed";" & @CRLF & _ "// "${distro_id}:${distro_codename}-backports";" & @CRLF & _ "};" & @CRLF & _ "" & @CRLF & _ "// Python regular expressions, matching packages to exclude from upgrading" & @CRLF & _ "Unattended-Upgrade::Package-Blacklist {" & @CRLF & _ " // The following matches all packages starting with linux-" & @CRLF & _ "// "linux-";" & @CRLF & _ "" & @CRLF & _ " // Use $ to explicitely define the end of a package name. Without" & @CRLF & _ " // the $, "libc6" would match all of them." & @CRLF & _ "// "libc6$";" & @CRLF & _ "// "libc6-dev$";" & @CRLF & _ "// "libc6-i686$";" & @CRLF & _ "" & @CRLF & _ " // Special characters need escaping" & @CRLF & _ "// "libstdc\+\+6$";" & @CRLF & _ "" & @CRLF & _ " // The following matches packages like xen-system-amd64, xen-utils-4.1," & @CRLF & _ " // xenstore-utils and libxenstore3.0" & @CRLF & _ "// "(lib)?xen(store)?";" & @CRLF & _ "" & @CRLF & _ " // For more information about Python regular expressions, see" & @CRLF & _ " // https://docs.python.org/3/howto/regex.html" & @CRLF & _ "};" & @CRLF & _ "" & @CRLF & _ "// This option controls whether the development release of Ubuntu will be" & @CRLF & _ "// upgraded automatically. Valid values are "true", "false", and "auto"." & @CRLF & _ "Unattended-Upgrade::DevRelease "auto";" & @CRLF & _ "" & @CRLF & _ "" & @CRLF & _ "##################################################################" & @CRLF & _ "#### /etc/cron.weekly/man-db ###" & @CRLF & _ "" & @CRLF & _ "#!/bin/sh" & @CRLF & _ "#" & @CRLF & _ "# man-db cron weekly" & @CRLF & _ "" & @CRLF & _ "set -e" & @CRLF & _ "" & @CRLF & _ "if [ -d /run/systemd/system ]; then" & @CRLF & _ " # Skip in favour of systemd timer." & @CRLF & _ " exit 0" & @CRLF & _ "fi" & @CRLF & _ "" & @CRLF & _ "iosched_idle=" & @CRLF & _ "# Don't try to change I/O priority in a vserver or OpenVZ." & @CRLF & _ "if ! egrep -q '(envID|VxID):.*[1-9]' /proc/self/status && \" & @CRLF & _ " ([ ! -d /proc/vz ] || [ -d /proc/bc ]); then" & @CRLF & _ " iosched_idle='--iosched idle'" & @CRLF & _ "fi" & @CRLF & _ "" & @CRLF & _ "if ! [ -d /var/cache/man ]; then" & @CRLF & _ " # Recover from deletion, per FHS." & @CRLF & _ " install -d -o man -g man -m 0755 /var/cache/man" & @CRLF & _ "fi" & @CRLF & _ "" & @CRLF & _ "# regenerate man database" & @CRLF & _ "if [ -x /usr/bin/mandb ]; then" & @CRLF & _ " # --pidfile /dev/null so it always starts; mandb isn't really a daemon," & @CRLF & _ " # but we want to start it like one." & @CRLF & _ " start-stop-daemon --start --pidfile /dev/null \" & @CRLF & _ " --startas /usr/bin/mandb --oknodo --chuid man \" & @CRLF & _ " $iosched_idle \" & @CRLF & _ " -- --quiet" & @CRLF & _ "fi" & @CRLF & _ "" & @CRLF & _ "exit 0" 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