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 = /(export )?const (.* \= \()(.*)(\).*\()(?'fileContent'(\n.*)+)\3\.(?'varName'[^}]*)\}(?'restOfPropLine'.*$)(?'restOfFileContent'(\n.*)+>\n\);)/m str = 'export const AffiliateAccountBIFields = (props) => ( <SimpleShowLayout {...props} variant="one"> <UrlField source="bi_url" options={{ target: \'_blank\' }} /> <ProtectedBIConfigField source="bi_settings" /> </SimpleShowLayout> ); export const AffiliateAccountGeneralFields = (props) => ( <SimpleShowLayout {...props}> <TextField source="name" /> <ReferenceField linkType="show" label="Platform Provider" addLabel source="platform_provider_id" reference="accounts/platform-providers" allowEmpty > <TextField addLabel source="name" /> </ReferenceField> <ReferenceField label="Company" addLabel source="company_id" reference="companies" linkType="show" > <TextField addLabel source="name" /> </ReferenceField> <AccountManagerField label="Account Manager" source="account_manager_id" addLabel /> <PortfolioField label="Portfolio" source="portfolio_id" addLabel /> <FunctionField label="Status" addLabel source="activity_status" render={(record) => { if (!record.activity_status) return null; const humanizedStatus = get( ACTIVITY_STATUS_OPTIONS, `${record.activity_status}.name` ); if (!humanizedStatus) { // eslint-disable-next-line no-console console.warn(`Cannot obtain humanized value for activity_status: ${record.activity_status}`); } return ( <TextField source="activity_status" record={{ ...record, activity_status: humanizedStatus || record.activity_status, }} /> ); }} /> <UrlField source="affiliate_system_link" options={{ target: \'_blank\' }} /> <CopyToClipboardField source="username"> <TextField source="username" /> </CopyToClipboardField> <ProtectedField source="password" /> <CopyToClipboardField source="email"> <TextField source="email" /> </CopyToClipboardField> <TextField source="security_question" /> <ProtectedField source="security_answer" /> <TextField source="type" /> <BooleanField source="tracking_enabled" /> <TextField source="tracking_variable_name" /> <TextField source="external_affiliate_id" /> <TextField source="revenue_posting_code" /> <BooleanField source="loss_carry_forward" /> <DateField source="updated_at" locales="en-GB" showTime /> <DateField source="created_at" locales="en-GB" showTime /> </SimpleShowLayout> ); export const AffiliateAccountTabs = (props) => { if (!props.record) { return null; } return ( <TabbedShowLayout> <AffiliateAccountGeneralFields {...props} label="General" /> <AffiliateAccountBrands {...props} label="Brands" /> <AffiliateAccountDeals {...props} label="Deals" /> {props.hasBIPermission && ( <AffiliateAccountBIFields {...props} label="BI Settings" /> )} </TabbedShowLayout> ); }; AffiliateAccountTabs.propTypes = { record: PropTypes.object, hasBIPermission: PropTypes.bool.isRequired, }; export const Show = (props) => ( <AutoLoginStatusDialog messages={messages}> <AORShow {...props} title={( <Title resource="Affiliate Account" type="show" buttons={[ <FavoriteButton record={{ _id: props.match.params.id }} resource={props.resource} style={{ height: \'25px\' }} />, ]} /> )} actions={( <ActionsPanel customButtons={[ <AutoLoginButton record={{ _id: props.match.params.id }} resource={props.resource} resourceConfig={autoLoginConfig} label="Auto Login" />, ]} /> )} > <AffiliateAccountTabs hasBIPermission={props.hasBIPermission} /> </AORShow> <NotesView isShow match={props.match} resource={props.resource} /> </AutoLoginStatusDialog> ); Show.propTypes = { match: PropTypes.shape({ params: PropTypes.shape({ id: PropTypes.string, }), }), resource: PropTypes.string, hasBIPermission: PropTypes.bool.isRequired, }; export default connect((state) => ({ hasBIPermission: checkPermission(state.auth.permissions, \'*\', \'bi_user\'), }))(Show); ' subst = '$1const $2{ ${varName}, ...$3 }$4${fileContent}${varName}}${restOfPropLine}${restOfFileContent}' result = str.gsub(re, subst) # Print the result of the substitution puts 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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html