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

Code Generator

Language

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)%5B%22[^ ]+%22%2C1%2C%22%22%2C%22(.*)%22%5D@googleapis.com").unwrap(); let string = "--batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%22124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM%22%2C1%2C%22%22%2C%22testuser1%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"testuser1@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi%22%2C1%2C%22%22%2C%22testuser1%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"testuser1@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221n89G34zW8jBWWCobxLCjdhlds-vjDNmR%22%2C1%2C%22%22%2C%22testuser1%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1n89G34zW8jBWWCobxLCjdhlds-vjDNmR/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"testuser1@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%22124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM%22%2C1%2C%22%22%2C%22sanityuser%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"sanityuser@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi%22%2C1%2C%22%22%2C%22sanityuser%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"sanityuser@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221n89G34zW8jBWWCobxLCjdhlds-vjDNmR%22%2C1%2C%22%22%2C%22sanityuser%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1n89G34zW8jBWWCobxLCjdhlds-vjDNmR/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"sanityuser@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%22124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM%22%2C1%2C%22%22%2C%22admin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"admin@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi%22%2C1%2C%22%22%2C%22admin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"admin@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221n89G34zW8jBWWCobxLCjdhlds-vjDNmR%22%2C1%2C%22%22%2C%22admin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1n89G34zW8jBWWCobxLCjdhlds-vjDNmR/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"admin@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%22124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM%22%2C1%2C%22%22%2C%22feadmin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/124I1eovpUwJR2Ce6sb4LbtSHgri5BJHM/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"feadmin@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi%22%2C1%2C%22%22%2C%22feadmin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1fbbSghayZHhIJBTSK-ZqQT6_gt_bfcpi/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"feadmin@gatewaybeatle.com\"} --batch7717900821286095411 Content-Type: application/http Content-Transfer-Encoding: binary Content-ID: <batch7717900821286095411+%5B%221n89G34zW8jBWWCobxLCjdhlds-vjDNmR%22%2C1%2C%22%22%2C%22feadmin%40gatewaybeatle%2Ecom%22%5D@googleapis.com> POST /drive/v2internal/files/1n89G34zW8jBWWCobxLCjdhlds-vjDNmR/permissions?fields=id%2Cname%2CemailAddress%2Crole%2CphotoLink%2CadditionalRoles%2Ctype%2CwithLink%2Cdomain%2CpermissionDetails%2Ccapabilities%2CselectableRoles%2Cview%2CinapplicableReason%2CexpirationDate%2Cdeleted%2CaudienceId%2CcustomerId%2CisStale&confirmed=false&sendNotificationEmails=true&languageCode=en&supportsTeamDrives=true&alt=json&key=AIzaSyC4JjdyoZPBZbhiXypJRsdhGicms9lgzoA X-JavaScript-User-Agent: google-api-javascript-client/1.1.0 X-Requested-With: XMLHttpRequest Content-Type: application/json X-Goog-Encode-Response-If-Executable: base64 X-Goog-AuthUser: 0 Authorization: SAPISIDHASH 1589278246_b2c8377eb040624a399411f2e7cea308088b32b3 X-ClientDetails: appVersion=5.0%20(Windows)&platform=Win32&userAgent=Mozilla%2F5.0%20(Windows%20NT%2010.0%3B%20WOW64%3B%20rv%3A68.0)%20Gecko%2F20100101%20Firefox%2F68.0 {\"additionalRoles\":[],\"role\":\"writer\",\"type\":\"user\",\"value\":\"feadmin@gatewaybeatle.com\"} --batch7717900821286095411-- "; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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/