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

Substitution

Processing...

Code Generator

Generated Code

#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox Local $sRegex = "(?m)(\/\/.*| ?\/\*[^]*?\*\/)(,?)$" Local $sString = "/**" & @CRLF & _ " * " & @CRLF & _ " * " & @CRLF & _ " * a multi-line example just for fun" & @CRLF & _ " */" & @CRLF & _ "" & @CRLF & _ "{" & @CRLF & _ " "compilerOptions": {" & @CRLF & _ " /* Visit https://aka.ms/tsconfig.json to read more about this file */" & @CRLF & _ "" & @CRLF & _ " /* Basic Options */" & @CRLF & _ " // "incremental": true, /* Enable incremental compilation */" & @CRLF & _ " "target": "ES6" /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', or 'ESNEXT'. */," & @CRLF & _ " "module": "commonjs" /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', or 'ESNext'. */," & @CRLF & _ " "lib": ["dom", "es6"] /* Specify library files to be included in the compilation. */," & @CRLF & _ " "allowJs": true /* Allow javascript files to be compiled. */," & @CRLF & _ " // "checkJs": true, /* Report errors in .js files. */" & @CRLF & _ " // "jsx": "preserve", /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */" & @CRLF & _ " "declaration": true /* Generates corresponding '.d.ts' file. */," & @CRLF & _ " "declarationMap": true /* Generates a sourcemap for each corresponding '.d.ts' file. */," & @CRLF & _ " // "sourceMap": true, /* Generates corresponding '.map' file. */" & @CRLF & _ " // "outFile": "./", /* Concatenate and emit output to single file. */" & @CRLF & _ " // "outDir": "./dist" /* Redirect output structure to the directory. */," & @CRLF & _ " // "rootDir": "./", /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */" & @CRLF & _ " // "composite": true, /* Enable project compilation */" & @CRLF & _ " // "tsBuildInfoFile": "./", /* Specify file to store incremental compilation information */" & @CRLF & _ " // "removeComments": true, /* Do not emit comments to output. */" & @CRLF & _ " // "noEmit": true, /* Do not emit outputs. */" & @CRLF & _ " // "importHelpers": true, /* Import emit helpers from 'tslib'. */" & @CRLF & _ " // "downlevelIteration": true, /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */" & @CRLF & _ " // "isolatedModules": true, /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */" & @CRLF & _ "" & @CRLF & _ " /* Strict Type-Checking Options */" & @CRLF & _ " "strict": true /* Enable all strict type-checking options. */," & @CRLF & _ " // "noImplicitAny": true, /* Raise error on expressions and declarations with an implied 'any' type. */" & @CRLF & _ " // "strictNullChecks": true, /* Enable strict null checks. */" & @CRLF & _ " // "strictFunctionTypes": true, /* Enable strict checking of function types. */" & @CRLF & _ " // "strictBindCallApply": true, /* Enable strict 'bind', 'call', and 'apply' methods on functions. */" & @CRLF & _ " // "strictPropertyInitialization": true, /* Enable strict checking of property initialization in classes. */" & @CRLF & _ " // "noImplicitThis": true, /* Raise error on 'this' expressions with an implied 'any' type. */" & @CRLF & _ " // "alwaysStrict": true, /* Parse in strict mode and emit "use strict" for each source file. */" & @CRLF & _ "" & @CRLF & _ " /* Additional Checks */" & @CRLF & _ " // "noUnusedLocals": true, /* Report errors on unused locals. */" & @CRLF & _ " // "noUnusedParameters": true, /* Report errors on unused parameters. */" & @CRLF & _ " // "noImplicitReturns": true, /* Report error when not all code paths in function return a value. */" & @CRLF & _ " // "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */" & @CRLF & _ "" & @CRLF & _ " /* Module Resolution Options */" & @CRLF & _ " // "moduleResolution": "node", /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */" & @CRLF & _ " "baseUrl": "./" /* Base directory to resolve non-absolute module names. */," & @CRLF & _ " "paths": {" & @CRLF & _ " /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */" & @CRLF & _ " /* TODO: Fix alias resolution with cypress */" & @CRLF & _ " "@lib": ["cypress/lib"]," & @CRLF & _ " "@lib/*": ["cypress/lib/*"]," & @CRLF & _ " "@log/browser": ["cypress/support/customCommands/browserLog"]," & @CRLF & _ " "@log/node": ["cypress/lib/nodeLog"]," & @CRLF & _ " "@tasks": ["cypress/plugins/tasks"]," & @CRLF & _ " "@tasks/*": ["cypress/plugins/tasks/*"]" & @CRLF & _ " }," & @CRLF & _ " // "rootDirs": [], /* List of root folders whose combined content represents the structure of the project at runtime. */" & @CRLF & _ " // "typeRoots": [], /* List of folders to include type definitions from. */" & @CRLF & _ " "types": ["node", "cypress", "./types"] /* Type declaration files to be included in compilation. */," & @CRLF & _ " // "allowSyntheticDefaultImports": true, /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */" & @CRLF & _ " "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */," & @CRLF & _ " // "preserveSymlinks": true, /* Do not resolve the real path of symlinks. */" & @CRLF & _ " // "allowUmdGlobalAccess": true, /* Allow accessing UMD globals from modules. */" & @CRLF & _ "" & @CRLF & _ " /* Source Map Options */" & @CRLF & _ " // "sourceRoot": "", /* Specify the location where debugger should locate TypeScript files instead of source locations. */" & @CRLF & _ " // "mapRoot": "", /* Specify the location where debugger should locate map files instead of generated locations. */" & @CRLF & _ " // "inlineSourceMap": true, /* Emit a single file with source maps instead of having a separate file. */" & @CRLF & _ " // "inlineSources": true, /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */" & @CRLF & _ "" & @CRLF & _ " /* Experimental Options */" & @CRLF & _ " // "experimentalDecorators": true, /* Enables experimental support for ES7 decorators. */" & @CRLF & _ " // "emitDecoratorMetadata": true, /* Enables experimental support for emitting type metadata for decorators. */" & @CRLF & _ "" & @CRLF & _ " /* Advanced Options */" & @CRLF & _ " "skipLibCheck": true /* Skip type checking of declaration files. */," & @CRLF & _ " "forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */," & @CRLF & _ " "resolveJsonModule": true," & @CRLF & _ " "noEmit": true // We should not be using transpiled code at all. We only need to run tsc to ensure type checking!" & @CRLF & _ " }," & @CRLF & _ " "include": ["cypress/**/*.ts", "npm-scripts/**/*.ts", "ops/**/*.ts", "cypress.json", "cypressRunner.ts", "customBootstrapCommand.ts"]," & @CRLF & _ " "exclude": ["**/*.ignore.*", "**/*ignore*/*", "build", "dist", "node_modules"]" & @CRLF & _ "}" & @CRLF & _ "" Local $sSubst = "$2" 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