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

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r"(?m)(export )?const (.* \= \()(.*)(\).*\()(?'fileContent'(\n.*)+)\3\.(?'varName'[^}]*)\}(?'restOfPropLine'.*$)(?'restOfFileContent'(\n.*)+>\n\);)").unwrap(); let string = "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); "; let substitution = "$1const $2{ ${varName}, ...$3 }$4${fileContent}${varName}}${restOfPropLine}${restOfFileContent}"; // result will be a String with the substituted value let result = regex.replace_all(string, substitution); println!("{}", 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 Rust, please visit: https://docs.rs/regex/latest/regex/