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"CIgcCursor.*<.*>\s*(\w*)[^}]*?(?:while|for)\s*\(.*?\n.*?(\{(?>[^{}]|(?-1))*\})") test_str = ("Return_t\n" "rgRoadNameChanges(Maneuver_o *pManeuverObj, rgManeuver_t *pManeuver, bool& bIsChanged)\n" "{\n" " Return_t Result;\n" " Sint_t iIndex;\n" " utSegment_t Seg;\n" " utSegmentInfo_t SegInfo;\n" " Uint_t nDist = 0;\n" " DBID_t prevNavFeatureID;\n" " DBID_t currDBID;\n" " CIgcCursor_Sdal<DBNavFeatureAndAttrs_t> cursorFeature(true);\n\n" " bIsChanged = false;\n" " DBID_SET_NULL(prevNavFeatureID);\n" " iIndex = pManeuver->RouteIndex;\n\n" " while (nDist < 800)\n" " {\n" " if ((Result = utRouteGetSegment(pManeuverObj->hRoute, &Seg, iIndex)) == SDAL_FAILURE)\n" " return NT_SUCCESS;\n\n" " if ((Result = utSegmentGetInfo(&Seg, &SegInfo, NULL)) == SDAL_FAILURE)\n" " return NT_TRACE(Result, NT_ERR_STR(\"rgRoadNameChanges: utSegmentGetInfo failed!\"));\n\n" " if ((Result = utSegmentGetDBID(&Seg, &currDBID, NULL)) == SDAL_FAILURE)\n" " return NT_TRACE(Result, NT_ERR_STR(\"rgRoadNameChanges: utSegmentGetDBID failed!\"));\n\n" " Result = iDbGetSegNavFeatures(&currDBID, 0, cursorFeature);\n\n" " if (Result > 0)\n" " {\n" " // Just comparing the first nav features for now. I don't know if we \n" " // need to check all against the other list in case the order of the \n" " // nav features changes. I'm assuming they'll stay the same order.\n" " if (!(++cursorFeature).NoMoreRecords())\n" " {\n" " if (!DBID_IS_NULL(prevNavFeatureID)\n" " && (iGuCompareDBIDsEqual(&prevNavFeatureID, &cursorFeature->navFeature.navFeatureID, GU_COMPARE_FULL_IDS) != 0))\n" " {\n" " bIsChanged = true;\n" " break;\n" " }\n" " utMemcpy(&prevNavFeatureID, &cursorFeature->navFeature.navFeatureID, sizeof(DBID_t));\n" " }\n" " }\n\n" " nDist += SegInfo.length;\n" " iIndex++;\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