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
No Match

/
/
gsi

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

re = /.*?Name: (?<name>.*?)\nversion: (?<num>.*?)\n.*?created on: (?<date>.*?)\n.*?/i str = 'Loading repository data... Reading installed packages... Information for patch sdksp3-rpm-201406: Name: sdksp3-rpm-201406 Version: 9435 Arch: noarch Vendor: maint-coord@suse.de Status: Needed Category: recommended Created On: Thu Jun 26 11:27:51 2014 Reboot Required: No Package Manager Restart Required: Yes Interactive: No Summary: YOU update for popt Description: This update for RPM provides the following fixes and enhancements: * Add query support for the new weak dependency tags used in SLE 12. (bnc#884373) * Remove harmful --target option passing from the configure macro. (bnc#870358) * Disable broken ldconfig skipping code. (bnc#725478) Additionally, one issue was fixed in the rpm-python sub-package: * Return a PyLong for installsize and archivesize if a PyInt would be negative. This could make createrepo(8) generate repository metadata with negative sizes for some packages. (bnc#882489) Provides: patch:sdksp3-rpm-201406 == 9435 Conflicts: popt-devel.x86_64 < 1.7-37.58.1 rpm-32bit.x86_64 < 4.4.2.3-37.58.1 rpm-devel.x86_64 < 4.4.2.3-37.58.1 Loading repository data... Reading installed packages... Information for patch sdksp3-rpm-201501: Name: sdksp3-rpm-201501 Version: 10143 Arch: noarch Vendor: maint-coord@suse.de Status: Needed Category: recommended Created On: Fri Jan 9 08:15:33 2015 Reboot Required: No Package Manager Restart Required: Yes Interactive: No Summary: Recommended update for rpm Description: This update for "rpm" fixes installation of packages when there are spaces in the path or file name and the option "--noglob" is used. Provides: patch:sdksp3-rpm-201501 == 10143 Conflicts: popt-devel.x86_64 < 1.7-37.62.9 rpm-32bit.x86_64 < 4.4.2.3-37.62.9 rpm-devel.x86_64 < 4.4.2.3-37.62.9 Loading repository data... Reading installed packages... Information for patch sdksp3-softwaremgmt-201503: Name: sdksp3-softwaremgmt-201503 Version: 10576 Arch: noarch Vendor: maint-coord@suse.de Status: Needed Category: recommended Created On: Tue Apr 7 09:29:23 2015 Reboot Required: No Package Manager Restart Required: Yes Interactive: No Summary: YOU update for the Software Update Stack Description: This collective update for the Software Update Stack provides several fixes and enhancements. libsatsolver: * Support product end-of-life attribute. (FATE#300591) libzypp: * Improve conflict message for locked packages. (bsc#828631) * Add Product::endOfLife attribute. (FATE#316172, FATE#300591) PackageKit: * When a proxy server is configured, a default route is not mandatory. (bsc#910462) rpm: * Allow noscripts and notriggers on verify. (bsc#803669) yast2-pkg-bindings: * Use alias from URL query parameter if present. (bsc#892431) zypper: * A date limit must ignore newer patch candidates. (bsc#919709) * Show locked packages in zypper summary. (FATE#318256) * Refresh plugin services on \'lr\' \'ls -r\' and \'ref\'. (bsc#893294, FATE#317863) * Enhance \'Digest verification failed\' dialog. (FATE#315008) * Add Product::endOfLife attribute. (FATE#316172, FATE#300591) Provides: patch:sdksp3-softwaremgmt-201503 == 10576 Conflicts: PackageKit-devel.x86_64 < 0.3.14-2.30.11 libpackagekit-glib10-devel.x86_64 < 0.3.14-2.30.11 libpackagekit-qt10.x86_64 < 0.3.14-2.30.11 libpackagekit-qt10-devel.x86_64 < 0.3.14-2.30.11 libsatsolver-devel.x86_64 < 0.17.9-0.5.2 libzypp-devel.x86_64 < 9.38.4-0.7.10 popt-devel.x86_64 < 1.7-37.63.64.1 rpm-32bit.x86_64 < 4.4.2.3-37.63.64.1 rpm-devel.x86_64 < 4.4.2.3-37.63.64.1 ruby-satsolver.x86_64 < 0.44.5-0.5.194 yast2-pkg-bindings-devel-doc.noarch < 2.17.59.2-0.8.13 Loading repository data... Reading installed packages... ' subst = '\\g<name> \\g<num> \\g<date>\\n' result = str.gsub(re, subst) # Print the result of the substitution puts 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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html