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

/
/
g

Test String

Substitution

Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "assertEquals\(([^,]+),\s(.+)\);" Local $sString = "package com.gdit.fwa.informant.model.definitions;" & @CRLF & _ "" & @CRLF & _ "import static org.junit.Assert.assertEquals;" & @CRLF & _ "" & @CRLF & _ "import org.junit.Test;" & @CRLF & _ "" & @CRLF & _ "import com.gdit.fwa.informant.model.base.definition.RelationalOperator;" & @CRLF & _ "import com.gdit.fwa.informant.model.base.definition.SqlConstants;" & @CRLF & _ "" & @CRLF & _ "@SuppressWarnings("static-method")" & @CRLF & _ "public class RelationalOperatorTest {" & @CRLF & _ "" & @CRLF & _ " @Test" & @CRLF & _ " public void testGetRelOperatorSql() {" & @CRLF & _ " assertEquals(RelationalOperator.DEFAULT.getRelOperatorSql(), "");" & @CRLF & _ " assertEquals(RelationalOperator.IS.getRelOperatorSql(), "IS");" & @CRLF & _ " assertEquals(RelationalOperator.IS_NOT.getRelOperatorSql(), "IS NOT");" & @CRLF & _ " assertEquals(RelationalOperator.EQUAL.getRelOperatorSql(), "=");" & @CRLF & _ " assertEquals(RelationalOperator.NOT_EQUAL.getRelOperatorSql(), "<>");" & @CRLF & _ " assertEquals(RelationalOperator.GREATER_THAN.getRelOperatorSql(), ">");" & @CRLF & _ " assertEquals(RelationalOperator.LESS_THAN.getRelOperatorSql(), "<");" & @CRLF & _ " assertEquals(RelationalOperator.GREATER_EQUAL.getRelOperatorSql(), ">=");" & @CRLF & _ " assertEquals(RelationalOperator.LESS_EQUAL.getRelOperatorSql(), "<=");" & @CRLF & _ " assertEquals(RelationalOperator.BETWEEN.getRelOperatorSql(), "BETWEEN");" & @CRLF & _ " assertEquals(RelationalOperator.IN.getRelOperatorSql(), "IN");" & @CRLF & _ " assertEquals(RelationalOperator.NOT_IN.getRelOperatorSql(), "NOT IN");" & @CRLF & _ " assertEquals(RelationalOperator.LIKE.getRelOperatorSql(), "LIKE");" & @CRLF & _ " assertEquals(RelationalOperator.NOT_LIKE.getRelOperatorSql(), "NOT LIKE");" & @CRLF & _ " assertEquals(RelationalOperator.SOUNDS_LIKE.getRelOperatorSql(), "SOUNDS LIKE");" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " @Test" & @CRLF & _ " public void testGetRelationalOperator() {" & @CRLF & _ " assertEquals(RelationalOperator.DEFAULT, RelationalOperator.getRelationalOperator(""));" & @CRLF & _ " assertEquals(RelationalOperator.IS, RelationalOperator.getRelationalOperator("IS"));" & @CRLF & _ " assertEquals(RelationalOperator.IS_NOT, RelationalOperator.getRelationalOperator("IS NOT"));" & @CRLF & _ " assertEquals(RelationalOperator.EQUAL, RelationalOperator.getRelationalOperator("="));" & @CRLF & _ " assertEquals(RelationalOperator.NOT_EQUAL, RelationalOperator.getRelationalOperator("<>"));" & @CRLF & _ " assertEquals(RelationalOperator.GREATER_THAN, RelationalOperator.getRelationalOperator(">"));" & @CRLF & _ " assertEquals(RelationalOperator.LESS_THAN, RelationalOperator.getRelationalOperator("<"));" & @CRLF & _ " assertEquals(RelationalOperator.GREATER_EQUAL, RelationalOperator.getRelationalOperator(">="));" & @CRLF & _ " assertEquals(RelationalOperator.LESS_EQUAL, RelationalOperator.getRelationalOperator("<="));" & @CRLF & _ " assertEquals(RelationalOperator.BETWEEN, RelationalOperator.getRelationalOperator("BETWEEN"));" & @CRLF & _ " assertEquals(RelationalOperator.IN, RelationalOperator.getRelationalOperator("IN"));" & @CRLF & _ " assertEquals(RelationalOperator.NOT_IN, RelationalOperator.getRelationalOperator("NOT IN"));" & @CRLF & _ " assertEquals(RelationalOperator.LIKE, RelationalOperator.getRelationalOperator("LIKE"));" & @CRLF & _ " assertEquals(RelationalOperator.NOT_LIKE, RelationalOperator.getRelationalOperator("NOT LIKE"));" & @CRLF & _ " assertEquals(RelationalOperator.SOUNDS_LIKE, RelationalOperator.getRelationalOperator("SOUNDS LIKE"));" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " @Test" & @CRLF & _ " public void testRelOpEqualityFunctions() {" & @CRLF & _ " for (RelationalOperator relOp : RelationalOperator.values()) {" & @CRLF & _ " if (relOp == RelationalOperator.IS || relOp == RelationalOperator.IS_NOT){" & @CRLF & _ " assertEquals(relOp.isEquality(), true);" & @CRLF & _ " assertEquals(relOp.getNullLogicOperator(), SqlConstants.OR);" & @CRLF & _ " assertEquals(relOp.getNullRelOperator(), RelationalOperator.IS);" & @CRLF & _ " assertEquals(relOp.getRelOperatorFilterSql(), RelationalOperator.IN.getRelOperatorSql());" & @CRLF & _ " } else {" & @CRLF & _ " assertEquals(relOp.isEquality(), false);" & @CRLF & _ " assertEquals(relOp.getNullLogicOperator(), SqlConstants.AND);" & @CRLF & _ " assertEquals(relOp.getNullRelOperator(), RelationalOperator.IS_NOT);" & @CRLF & _ " assertEquals(relOp.getRelOperatorFilterSql(), RelationalOperator.NOT_IN.getRelOperatorSql());" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " @Test" & @CRLF & _ " @SuppressWarnings("deprecation")" & @CRLF & _ " public void testGetNullValue() {" & @CRLF & _ " assertEquals(RelationalOperator.getNullValue(), SqlConstants.NULL);" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ " @Test" & @CRLF & _ " public void testGetNullClause() {" & @CRLF & _ " for (RelationalOperator relOp : RelationalOperator.values()) {" & @CRLF & _ " switch (relOp) {" & @CRLF & _ " case IS:" & @CRLF & _ " case EQUAL:" & @CRLF & _ " assertEquals(relOp.getNullClause("Test"), " OR Test IS null");" & @CRLF & _ " break;" & @CRLF & _ " case IS_NOT:" & @CRLF & _ " case NOT_EQUAL:" & @CRLF & _ " assertEquals(relOp.getNullClause("Test"), " AND Test IS NOT null");" & @CRLF & _ " break;" & @CRLF & _ " default:" & @CRLF & _ " assertEquals(relOp.getNullClause("Test"), "");" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ " }" & @CRLF & _ "" & @CRLF & _ "}" & @CRLF & _ "" Local $sSubst = "assertEquals\($2\, $1\);" Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst) MsgBox($MB_SYSTEMMODAL, "Result", $sResult)

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 AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm