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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(.*[[:space:]]GRAVE:.*)", flags=re.MULTILINE) test_str = ("INFORMAZIONI: Parsing jar:file:/workarea/apache-tomcat/apache-tomcat-7.0.47_GA/webapps/GestioneAutorizzazioni/WEB-INF/lib/zkex-6.5.6.jar!/metainfo/zk/zk.xml\n" "lug 26, 2022 10:30:25 PM org.zkoss.zk.ui.sys.ConfigParser parse:269\n" "INFORMAZIONI: Parsing jar:file:/workarea/apache-tomcat/apache-tomcat-7.0.47_GA/webapps/GestioneAutorizzazioni/WEB-INF/lib/zkmax-6.5.6.jar!/metainfo/zk/zk.xml\n" "lug 26, 2022 10:30:25 PM org.zkoss.zk.ui.sys.ConfigParser parse:269\n" "INFORMAZIONI: Parsing jndi:/localhost/GestioneAutorizzazioni/WEB-INF/zk.xml\n" "lug 26, 2022 10:30:25 PM org.zkoss.zk.ui.http.WebManager <init>:172\n" "INFORMAZIONI: Parsing file:///workarea/apache-tomcat/tomcatGA/confapps/GestioneAutorizzazioni/zk-production.xml\n" "lug 26, 2022 10:30:25 PM org.zkoss.zk.ui.http.WebManager <init>:179\n" "GRAVE: File not found: file:///workarea/apache-tomcat/tomcatGA/confapps/GestioneAutorizzazioni/zk-production.xml\n" "lug 26, 2022 10:30:26 PM org.zkoss.zk.ui.metainfo.DefinitionLoaders parseLang:410\n" "AVVERTENZA: Component jasperreport ignored. Reason: unable to load org.zkoss.zkex.zul.Jasperreport due to java.lang.NoClassDefFoundError: net/sf/jasperreports/engine/JRDataSource\n\n" "Configuring Spring Security Core ...\n" "... finished configuring Spring Security Core\n\n" "amministrazione-database: doWithSpring\n" "anagrafe-soggetti: doWithSpring\n" "struttura-organizzativa: doWithSpring\n" "AmministrazioneDatabaseBootStrap: validate\n" "lug 26, 2022 10:30:56 PM org.apache.catalina.startup.HostConfig deployWAR\n" "INFORMAZIONI: Deploying web application archive /workarea/apache-tomcat/apache-tomcat-7.0.47_GA/webapps/probe.war\n" "lug 26, 2022 10:30:58 PM org.apache.catalina.startup.HostConfig deployWAR\n\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html