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

`
`
gm

Test String

Code Generator

Language

Generated Code

use strict; my $str = '-- -- Dumping data for table `SOME_TABLE` -- LOCK TABLES `SOME_TABLE` WRITE; /*!40000 ALTER TABLE `SOME_TABLE` DISABLE KEYS */; /*!40000 ALTER TABLE `SOME_TABLE` ENABLE KEYS */; UNLOCK TABLES; /*!50003 SET @saved_cs_client = @@character_set_client */ ; /*!50003 SET @saved_cs_results = @@character_set_results */ ; /*!50003 SET @saved_col_connection = @@collation_connection */ ; /*!50003 SET character_set_client = utf8 */ ; /*!50003 SET character_set_results = utf8 */ ; /*!50003 SET collation_connection = utf8_general_ci */ ; /*!50003 SET @saved_sql_mode = @@sql_mode */ ; /*!50003 SET sql_mode = \'ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION\' */ ; DELIMITER ;; /*!50003 CREATE*/ /*!50017 */ /*!50003 TRIGGER SOME_TABLE_BU BEFORE UPDATE ON SOME_TABLE FOR EACH ROW BEGIN IF (OLD.DUE_DATE<>NEW.DUE_DATE) THEN SET NEW.COUNT=0; INSERT INTO SOME_TABLE_RESET_COUNT(SOME_TABLE_ID,CAL_DUE_DATE,COUNT,USER_ID) VALUES(OLD.ID,OLD.DUE_DATE,OLD.CYCLE_COUNT,NEW.CAL_BY); END IF; END */;; DELIMITER ; /*!50003 SET sql_mode = @saved_sql_mode */ ; /*!50003 SET character_set_client = @saved_cs_client */ ; /*!50003 SET character_set_results = @saved_cs_results */ ; /*!50003 SET collation_connection = @saved_col_connection */ ; /*!50003 SET @saved_cs_client = @@character_set_client */ ; /*!50003 SET @saved_cs_results = @@character_set_results */ ; /*!50003 SET @saved_col_connection = @@collation_connection */ ; /*!50003 SET character_set_client = utf8 */ ; /*!50003 SET character_set_results = utf8 */ ; /*!50003 SET collation_connection = utf8_general_ci */ ; /*!50003 SET @saved_sql_mode = @@sql_mode */ ; /*!50003 SET sql_mode = \'NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION\' */ ; DELIMITER ;; /*!50003 CREATE*/ /*!50017 */ /*!50003 TRIGGER SOME_TABLE_AU AFTER UPDATE ON SOME_TABLE FOR EACH ROW BEGIN IF IFNULL(OLD.RESET_REASON,\'\') <> IFNULL(NEW.RESET_REASON,\'\') THEN INSERT INTO SOME_TABLE_RESET_NEXT_DUE(REASON,SOME_TABLE_ID,NEW_CAL_DATE,OLD_CAL_DATE) VALUES(NEW.RESET_REASON,NEW.ID,NEW.DUE_DATE,OLD.DUE_DATE); END IF; END */;; DELIMITER ; /*!50003 SET sql_mode = @saved_sql_mode */ ; /*!50003 SET character_set_client = @saved_cs_client */ ; /*!50003 SET character_set_results = @saved_cs_results */ ; /*!50003 SET collation_connection = @saved_col_connection */ ;'; my $regex = qr`(DELIMITER ;;[\S\s]*?DELIMITER ;)`mp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html