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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Generated Code

$re = '/(const |)brand = await Faker\.\w+\((DefaultBrand)\).build\(\);((.|\n)+?)(?=defaultCmsSettingsFakeFactory)defaultCmsSettingsFakeFactory\(\)\.build(..)((.|\n)+?): (?=BrandSpecifics)(BrandSpecifics\.[\w_]+)/m'; $str = ' beforeAll(async () => { const brand = await Faker.makeCmsFactory(DefaultBrand).build(); TestBed.configureTestingModule({ imports: [ResponsibleGamingPageDepositLimitSubpageContainerTestingModule, ContainersInitialTestingModule], providers: [ { provide: Brand, useValue: brand }, { provide: CMS_SETTINGS, useValue: defaultCmsSettingsFakeFactory().build() }, ], }); const cmsClientService = TestBed.inject(CmsClientService); const cmsSlugger = TestBed.inject(CmsSluggerService); const resultSlug = cmsSlugger.buildSlug({ brandSpecific: BrandSpecifics.BOO_CASINO, metaContentType: MetaContentTypes.CONTENT_SECTION, appContentType: \'brand\', property: \'0\', instanceName: \'0\', }); const result = await cmsClientService.getContent(resultSlug, LocaleNames.EN, false, 10); const getContentBehavior = TestBed.inject(GetContentBehavior); const config = (await getContentBehaviorConfigFakeFactory({ result, tags: {} })).build(); const actions = await getContentBehavior.run(config); const store = TestBed.inject(Store); actions.forEach((action) => store.dispatch(action)); await TestBed.compileComponents(); fixture = TestBed.createComponent(ResponsibleGamingPageDepositLimitSubpageContainer); component = fixture.componentInstance; fixture.detectChanges(); }); beforeAll(async () => { const brand = await Faker.makeCmsFactory(DefaultBrand).build(); TestBed.configureTestingModule({ imports: [LoginDialogContainerTestingModule, ContainersInitialTestingModule], providers: [ { provide: Brand, useValue: brand }, { provide: CMS_SETTINGS, useValue: defaultCmsSettingsFakeFactory().build() }, ], }); const cmsClientService = TestBed.inject(CmsClientService); const cmsSlugger = TestBed.inject(CmsSluggerService); const resultSlug = cmsSlugger.buildSlug({ brandSpecific: BrandSpecifics.BOO_CASINO, metaContentType: MetaContentTypes.CONTENT_SECTION, appContentType: \'brand\', property: \'0\', instanceName: \'0\', }); const result = await cmsClientService.getContent(resultSlug, LocaleNames.EN, false, 10); const getContentBehavior = TestBed.inject(GetContentBehavior); const config = (await getContentBehaviorConfigFakeFactory({ result, tags: {} })).build(); const actions = await getContentBehavior.run(config); const store = TestBed.inject(Store); actions.forEach((action) => store.dispatch(action)); await TestBed.compileComponents(); fixture = TestBed.createComponent(LoginDialogContainer); component = fixture.componentInstance; fixture.detectChanges(); }); beforeAll(async () => { const brand = await Faker.makeCmsFactory(DefaultBrand).build(); TestBed.configureTestingModule({ imports: [NewVersionNoticeContainerTestingModule, ContentStoreTestingModule, ContainersInitialTestingModule], providers: [ { provide: Brand, useValue: brand }, { provide: CMS_SETTINGS, useValue: defaultCmsSettingsFakeFactory().build() }, ], }); const cmsClientService = TestBed.inject(CmsClientService); const cmsSlugger = TestBed.inject(CmsSluggerService); const resultSlug = cmsSlugger.buildSlug({ brandSpecific: BrandSpecifics.BOO_CASINO, metaContentType: MetaContentTypes.CONTENT_SECTION, appContentType: \'brand\', property: \'0\', instanceName: \'0\', }); const result = await cmsClientService.getContent(resultSlug, LocaleNames.EN, false, 10); const getContentBehavior = TestBed.inject(GetContentBehavior); const config = (await getContentBehaviorConfigFakeFactory({ result, tags: {} })).build(); const actions = await getContentBehavior.run(config); const store = TestBed.inject(Store); actions.forEach((action) => store.dispatch(action)); await TestBed.compileComponents(); fixture = TestBed.createComponent(NewVersionNoticeContainer); component = fixture.componentInstance; fixture.detectChanges(); });'; $subst = "const brandSpecific = $8;\n $1brand = await Faker.makeCmsFactory($2, brandSpecific).build();$3 defaultCmsSettingsFakeFactory().build({ brandSpecific })$4$6"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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