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

/
/
si

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"name\s+?z155e4d1dde106c_point_test.+?(?<!meta)data\s*\".+?from\s+([^\s]+?)\"" test_str = ("MAP\n" " CONFIG \"MS_ERRORFILE\" \"/srv/mapservices/mapfiles/tmp/155e4d1dde106c.log\"\n" " DEBUG 5\n" " IMAGETYPE PNG\n" " SIZE 1600 800\n" " STATUS ON\n\n" " WEB\n" " METADATA\n" " \"wms_title\" \"Generated_Mapfile\"\n" " \"wms_onlineresource\" \"http://142.207.151.5/cgi-bin/mapserv?map=/srv/portal/www/Mapservices/mapfiles/TSAZones.map&version=1.0.0&service=wms\"\n" " \"wms_srs\" \"EPSG:3005 EPSG:4269 EPSG:3857\"\n" " \"wms_enable_request\" \"*\"\n" " \"wms_feature_info_mime_type\" \"text/html\"\n" " END\n" " QUERYFORMAT text/html\n" " END\n\n\n" " PROJECTION\n" " \"init=epsg:3005\"\n" " END\n\n" " OUTPUTFORMAT\n" " NAME png\n" " DRIVER AGG/PNG\n" " MIMETYPE \"image/png\"\n" " IMAGEMODE RGBA\n" " EXTENSION \"png\"\n" " FORMATOPTION \"GAMMA=0.75\"\n" " TRANSPARENT ON\n" " END\n" " LAYER\n" " DEBUG 5\n" " NAME z155e4d1dde106c_point_test\n" " DUMP TRUE\n" " TEMPLATE \"querytemplate.html\" \n\n" " PROJECTION\n" " \"init=epsg:3005\"\n" " END\n\n" " METADATA\n" " \"wms_srs\" \"EPSG:3005\"\n" " \"title\" \"TSA Zones\"\n" " \"wms_title\" \"TSA Zones\"\n" " \"wms_include_items\" \"all\" \n" " \"gml_include_items\" \"all\" \n" " END\n\n" " TYPE POINT\n" " CONNECTIONTYPE POSTGIS\n" " CONNECTION \"host=127.0.0.1 dbname=stewardship user=portal_readwrite password=portal_readwrite\"\n" " DATA \"wkb_geometry from z155e4d1dde106c_point_test\"\n\n" " \n" " CLASS\n" " STYLE\n" " COLOR 59 189 57 \n" " OUTLINECOLOR 147 155 48\n" " OPACITY 100\n" " END\n" " END\n" "END\n" "LAYER\n" " DEBUG 5\n" " NAME z155e4d1dde106c_poly_test1\n" " DUMP TRUE\n" " TEMPLATE \"querytemplate.html\" \n\n" " PROJECTION\n" " \"init=epsg:3005\"\n" " END\n\n" " METADATA\n" " \"wms_srs\" \"EPSG:3005\"\n" " \"title\" \"TSA Zones\"\n" " \"wms_title\" \"TSA Zones\"\n" " \"wms_include_items\" \"all\" \n" " \"gml_include_items\" \"all\" \n" " END\n\n" " TYPE POLYGON\n" " CONNECTIONTYPE POSTGIS\n" " CONNECTION \"host=127.0.0.1 dbname=stewardship user=portal_readwrite password=portal_readwrite\"\n" " DATA \"wkb_geometry from z155e4d1dde106c_poly_test1\"\n\n" " \n" " CLASS\n" " STYLE\n" " COLOR 121 71 143 \n" " OUTLINECOLOR 96 133 94\n" " OPACITY 100\n" " END\n" " END\n" "END\n" "END") matches = re.search(regex, test_str, re.DOTALL | re.IGNORECASE) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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