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

/
/
s

Test String

Code Generator

Language

Generated Code

$re = '/desc\s*"(((?!").)*)((?!\n).)*\n{1}task\s*:(((?!\n).)*)do(((?!\nend).)*)\nend/s'; $str = 'import \'cloud2/cloud2.rb\' desc "transfer db from current location to local and new dev" task :fulldbtransfer => [ :dbdown, :dbup, :dbup_live,] $comps_db = [\'prube_yalecomps\'] $tnew_dbs = [ \'prube_yaletnew_drama_prod\', \'prube_yaletnew_summer_cabaret_prod\', \'prube_yaletnew_cabaret_prod\', \'prube_yaletnew_music_prod\', \'prube_yaletnew_rep_prod\'] $new_tnew_dbs = [ \'prube_yaletnew_drama\', \'prube_yaletnew_summer_cabaret\', \'prube_yaletnew_cabaret\', \'prube_yaletnew_music\', \'prube_yaletnew_rep\'] all_erube_dbs = $comps_db + $tnew_dbs desc "Transfer Database, complete with tunnel setup and teardown" task :dbdown do all_erube_dbs.each do |database_name| cloud2_mysqldump do tunnel_host \'cumulus-www-master-pub.rs.lynch2.com\' tunnel_user \'www\' db_host \'cumulus-db-master.rs.lynch2.com\' skip_secure_auth true db_user \'mysql\' db_pass \'mysql\' db_name " file_prefix \'SOURCE_\' ignored_tables [\'cache\',\'hits\',\'debug\',\'sessionvars\',\'sessions\'] end end end task :dbsandr do dbname = "prube_yalecomps" bucket_prefix = "comps" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ ] replace_str [ ] end dbname = "prube_yaletnew_drama_prod" bucket_prefix = "drame" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ \'prube_yaletnew_drama_prod\', ] replace_str [ "prube_yaletnew_drama", ] end dbname = "prube_yaletnew_summer_cabaret_prod" bucket_prefix = "summer-cabaret" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ \'prube_yaletnew_summer_cabaret_prod\', ] replace_str [ \'prube_yaletnew_summer_cabaret\', ] end dbname = "prube_yaletnew_cabaret_prod" bucket_prefix = "cabaret" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ \'prube_yaletnew_cabaret_prod\', ] replace_str [ \'prube_yaletnew_cabaret\', ] end dbname = "prube_yaletnew_music_prod" bucket_prefix = "music" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ \'prube_yaletnew_music_prod\', ] replace_str [ \'prube_yaletnew_music\', ] end dbname = "prube_yaletnew_rep_prod" bucket_prefix = "rep" cloud2_sed do source_file "db-tools/SOURCE_mysqldump_ dest_file "db-tools/CLOUD2_ find_str [ \'prube_yaletnew_rep_prod\', ] replace_str [ \'prube_yaletnew_rep\', ] end end desc "Send Database to tigard-dev-rds" task :dbup do upload_dbs "reston-dev-rds.aws.lynch2.com" end desc "Send Database to tigard-mail2-rds" task :dbup_live do upload_dbs "reston-live-rds.aws.lynch2.com" end def upload_dbs (dbhost) $comps_db.each do |database_name| cloud2_mysql do db_host dbhost db_user \'mysql\' db_pass \'mysql\' db_name "mysql" sql_files ["CLOUD2_ end cloud2_mysql do db_host dbhost db_user \'mysql\' db_pass \'mysql\' db_name " sql_files ["erube_upgrade.sql"] end end $new_tnew_dbs.each do |database_name| cloud2_mysql do db_host dbhost db_user \'mysql\' db_pass \'mysql\' db_name "mysql" sql_files ["CLOUD2_ end cloud2_mysql do db_host dbhost db_user \'mysql\' db_pass \'mysql\' db_name " sql_files ["tnew_erube_upgrade.sql"] end end end '; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($matches);

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php