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

/
/
g

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#"\"(\w+)\"\s:"#).unwrap(); let string = "{ \"eventid\" : \"a35bcc79-2411-49b3-8f45-537fd46dab96\" , \"visitorid\" : \"014db7ee44bc0024bbbe6241eedc0606c003f06400bd0\" , \"eventtime\" : 1434594187000 , \"useragent\" : \"Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/43.0.2357.124 Safari/537.36\" , \"pageurl_full_url\" : \"https://store.trendmicro-europe.com/store\" , \"pageurl_query_params_env\" : \"BASE\" , \"pageurl_query_params_id\" : \"ThankYouPage\" , \"pageurl_query_params_action\" : \"DisplayPage\" , \"pageurl_query_params_reqid\" : \"13233624029\" , \"pageurl_query_params_locale\" : \"de_DE\" , \"pageurl_query_params_siteid\" : \"tmemea\" , \"pageurl_querystring\" : \"id=ThankYouPage&Env=BASE&Action=DisplayPage&reqID=13233624029&Locale=de_DE&SiteID=tmemea\" , \"pageurl_scheme\" : \"https\" , \"pageurl_domain\" : \"store.trendmicro-europe.com\" , \"pageurl_path\" : \"/store\" , \"referrerurl_full_url\" : \"https://store.trendmicro-europe.com/store?Action=DisplayPage&Env=BASE&Locale=de_DE&SiteID=tmemea&id=ThankYouPage&reqID=13233624029\" , \"referrerurl_query_params_action\" : \"DisplayPage\" , \"referrerurl_query_params_env\" : \"BASE\" , \"referrerurl_query_params_locale\" : \"de_DE\" , \"referrerurl_query_params_siteid\" : \"tmemea\" , \"referrerurl_query_params_id\" : \"ThankYouPage\" , \"referrerurl_query_params_reqid\" : \"13233624029\" , \"referrerurl_querystring\" : \"Action=DisplayPage&Env=BASE&Locale=de_DE&SiteID=tmemea&id=ThankYouPage&reqID=13233624029\" , \"referrerurl_scheme\" : \"https\" , \"referrerurl_domain\" : \"store.trendmicro-europe.com\" , \"referrerurl_path\" : \"/store\" , \"dom_title\" : \"Trend Micro Online-Shop - Bestellung abgeschlossen\" , \"dom_viewport_width\" : \"1920\" , \"dom_viewport_height\" : \"993\" , \"udo_internal_product_category\" : \"[ \\\"SEC\\\"]\" , \"udo_channel_closer\" : \"Other\" , \"udo_product_id\" : \"[ \\\"206411300\\\"]\" , \"udo_customurl\" : \"/checkout/de_DE/order-completed\" , \"udo__corder\" : \"13233624029\" , \"udo_channel_originator_credit\" : \"0\" , \"udo_as_page_name\" : \"trend store : checkout : thank you page\" , \"udo__cquan\" : \"[ \\\"1\\\"]\" , \"udo_internal_products_array\" : \"[ \\\"SEC \\\" , \\\" MR \\\" , \\\" NFQ \\\" , \\\" 2YR \\\" , \\\" 1PC \\\" , \\\" AR Off\\\"]\" , \"udo__ctax\" : \"9.57\" , \"udo_vis_random\" : \"70618350058794024\" , \"udo_event_value\" : \"1\" , \"udo_channel_category_closer\" : \"other\" , \"udo_customer_email\" : \"hagensturmwut@web.de\" , \"udo_ut_profile\" : \"main\" , \"udo_internal_renewal_type\" : \"[ \\\"AR Off\\\"]\" , \"udo__cprice\" : \"[ \\\"50.35\\\"]\" , \"udo_as_product_name\" : \"[ \\\"Trend Micro Internet Security\\\"]\" , \"udo_vis_perm_id_2\" : \"014db7ee44bc0024bbbe6241eedc0606c003f06400bd0\" , \"udo__ccurrency\" : \"EUR\" , \"udo__csku\" : \"[ \\\"TI-CIWW-M8X\\\"]\" , \"udo_referrer_eq_domain\" : \"false\" , \"udo_internal_customer_journey\" : \"[ \\\"\\\"]\" , \"udo__ccustid\" : \"435297354602\" , \"udo_as_page_type\" : \"checkout\" , \"udo_product_category\" : \"[ \\\"All Products\\\"]\" , \"udo_site_currency\" : \"EUR\" , \"udo_vis_session_id_2\" : \"1434593949895\" , \"udo_as_page_site_name\" : \"trend store\" , \"udo_channel_closer_credit\" : \"0\" , \"udo__cprod\" : \"[ \\\"206411300\\\"]\" , \"udo_event_category\" : \"E-Commerce\" , \"udo_order_shipping\" : \"0.00\" , \"udo_product_quantity_total\" : \"1\" , \"udo_order_payment_type\" : \"PayPal\" , \"udo__csubtotal\" : \"50.35\" , \"udo_ut_env\" : \"prod\" , \"udo__cship\" : \"0.00\" , \"udo__t_session_id\" : \"1434593949895\" , \"udo_channel_path\" : \"Other\" , \"udo__cpdisc\" : \"[ \\\"\\\"]\" , \"udo__cprodname\" : \"[ \\\"Trend Micro Internet Security\\\"]\" , \"udo__t_visitor_id\" : \"014e047678c7001938f5bd7dcd6d0606d00a006500bd0\" , \"udo_page_type\" : \"checkout\" , \"udo_customer_id\" : \"435297354602\" , \"udo_as_product_consumer_vs_business\" : \"[ \\\"consumer\\\"]\" , \"udo_channel_category_influencer\" : \"other\" , \"udo_event_action\" : \"Order Confirmation\" , \"udo_site_region\" : \"DE\" , \"udo_order_subtotal\" : \"50.35\" , \"udo__ccat\" : \"[ \\\"All Products\\\"]\" , \"udo_internal_sub_channel_id\" : \"[ \\\"NFQ\\\"]\" , \"udo_product_list_price\" : \"[ \\\"79.90\\\"]\" , \"udo_order_total\" : \"59.92\" , \"udo_load_rule_google_universal_analytics\" : \"true\" , \"udo_internal_product_subscription_length\" : \"[ \\\"2YR\\\"]\" , \"udo_ut_event\" : \"view\" , \"udo_channel_category_path\" : \"other\" , \"udo__pathname1\" : \"store\" , \"udo_channel_influencer_credit\" : \"0\" , \"udo_load_rules_tags_to_fire\" : \"gua_UA-36872905-3,marketo\" , \"udo_page_name\" : \"ThankYouPage\" , \"udo_order_currency\" : \"EUR\" , \"udo__cbrand\" : \"[ ]\" , \"udo_ut_version\" : \"ut4.36.201506171459\" , \"u \"gua_UA-36872905-3,marketo\" , \"udo_page_name\" : \"ThankYouPage\" , \"udo_order_currency\" : \"EUR\" , \"udo__cbrand\" : \"[ ]\" , \"udo_ut_version\" : \"ut4.36.201506171459\" , \"u do_cross_vis_session_ids\" : \"available\" , \"udo_product_name\" : \"[ \\\"Trend Micro Internet Security\\\"]\" , \"udo_product_quantity\" : \"[ \\\"1\\\"]\" , \"udo_channel_influencer\" : \"Other\" , \"udo_ut_account\" : \"trendmicro\" , \"udo_order_id\" : \"13233624029\" , \"udo_tealium_visitor_id_override\" : \"014e047678c7001938f5bd7dcd6d0606d00a006500bd0\" , \"udo__ctotal\" : \"59.92\" , \"udo_order_tax\" : \"9.57\" , \"udo_product_unit_price\" : \"[ \\\"50.35\\\"]\" , \"udo_channel_originator\" : \"Other\" , \"udo_internal_number_of_devices\" : \"[ \\\"1PC\\\"]\" , \"udo_order_discount\" : \"0.00\" , \"udo_channel_category_originator\" : \"other\" , \"udo__ccat2\" : \"[ ]\" , \"udo_url_wo_qs\" : \"https://store.trendmicro-europe.com/store\" , \"udo_load_rule_audiencestream\" : \"true\" , \"udo_device_detailed\" : \"desktop\" , \"udo_ve_basket_html_generated\" : \"true\" , \"udo_category\" : \"[ \\\"Trend Micro Internet Security\\\"]\" , \"udo_product_sku\" : \"[ \\\"TI-CIWW-M8X\\\"]\" , \"udo_device\" : \"desktop\" , \"udo_internal_product_name\" : \"[ \\\"SEC | MR | NFQ | 2YR | 1PC | AR Off\\\"]\" , \"udo_internal_product_id\" : \"[ \\\"MR\\\"]\" , \"udo_product_discount\" : \"[ \\\"\\\"]\" , \"js_utag_cfg_path\" : \"//tags.tiqcdn.com/utag/trendmicro/main/prod/\" , \"js_datalayer\" : \"[ \\\"{ \\\\\\\"customURL\\\\\\\" : \\\\\\\"/checkout/de_DE/order-completed\\\\\\\"}\\\" , \\\"{ \\\\\\\"gtm.start\\\\\\\" : 1434594193626 , \\\\\\\"event\\\\\\\" : \\\\\\\"gtm.js\\\\\\\"}\\\" , \\\"{ \\\\\\\"event\\\\\\\" : \\\\\\\"sale\\\\\\\" , \\\\\\\"transactionId\\\\\\\" : \\\\\\\"13233624029\\\\\\\" , \\\\\\\"transactionAffiliation\\\\\\\" : \\\\\\\"tmemea\\\\\\\" , \\\\\\\"transactionTotal\\\\\\\" : 50.35 , \\\\\\\"transactionTax\\\\\\\" : 9.57 , \\\\\\\"transactionShipping\\\\\\\" : 0 , \\\\\\\"transactionCurrency\\\\\\\" : \\\\\\\"EUR\\\\\\\" , \\\\\\\"transactionProducts\\\\\\\" : [ { \\\\\\\"sku\\\\\\\" : \\\\\\\"206411300\\\\\\\" , \\\\\\\"name\\\\\\\" : \\\\\\\"SEC | MR | NFQ | 2YR | 1PC | AR Off\\\\\\\" , \\\\\\\"category\\\\\\\" : \\\\\\\"All Products\\\\\\\" , \\\\\\\"price\\\\\\\" : 50.35 , \\\\\\\"quantity\\\\\\\" : 1}]}\\\" , \\\"{ \\\\\\\"event\\\\\\\" : \\\\\\\"gtm.dom\\\\\\\"}\\\"]\" , \"firstpartycookies_utag_main_dc_event\" : \"34\" , \"firstpartycookies_utag_main__ss\" : \"0\" , \"firstpartycookies_utag_main__st\" : \"1434595993661\" , \"firstpartycookies_utag_ulog__vi\" : \"014e0476791e005f54a93f2d05640606d00a006500bd0\" , \"firstpartycookies_utag_ulog__fs\" : \"1434593949982\" , \"firstpartycookies_utag_main_dc_visit\" : \"1\" , \"firstpartycookies_fcr\" : \"http://www.trendmicro.de/produkte/internet-sicherheitssoftware/index.html\" , \"firstpartycookies_optimizelyenduserid\" : \"oeu1434593947489r0.8301690202206373\" , \"firstpartycookies_fcp\" : \"C=0&T=1434593950386&DTO=1434593949534&U=1401563069&V=1434594127078\" , \"firstpartycookies_mbox\" : \"session#1434593944791-800726#1434596054|PC#1434593944791-800726#1497666194|check#true#1434594254\" , \"firstpartycookies_op_browser\" : \"safari_537.36\" , \"firstpartycookies__gat_tealium\" : \"1\" , \"firstpartycookies__gat_trend\" : \"1\" , \"firstpartycookies_op_browserhigh\" : \"safari\" , \"firstpartycookies_utag_main_ses_id\" : \"1434593949895\" , \"firstpartycookies__ga\" : \"GA1.2.505298797.1433309956\" , \"firstpartycookies_fcc\" : \"X=C1401563069&Y=1434594127083&FV=18&H=1434594127078&fcTHR=shop.digitalriver.com}www.trendmicro-europe.com,www.digitalriver.com}www.trendmicro-europe.com,store.digitalriver.com}www.trendmicro-europe.com,store.trendmicro-europe.com}www.trendmicro-europe.com&Z=3&vis=m14z1#s3#e504211zde_DE#s4#m14z2&E=220062&F=0&I=1434594152851\" , \"firstpartycookies_utag_main__sn\" : \"1\" , \"firstpartycookies_gc_ss_tmemea\" : \"19B4F75E4FEC9468A2E6AC258A4D5F1F07C358164CAB37A182BBD6FD4BC11C783EB8C3E5FE6E2CEC\" , \"firstpartycookies_utag_ulog__cs\" : \"1434593949982\" , \"firstpartycookies_trend_ecommerce_previousurl\" : \"store.trendmicro-europe.com/store?Action=DisplayPage&Env=BASE&Locale=de_DE&SiteID=tmemea&id=ThankYouPage&reqID=13233624029\" , \"firstpartycookies_visitor_id\" : \"971D4E8DFAED4367957BC5516507C190A4B4FF01327F780F\" , \"firstpartycookies_fcoos\" : \"fcOptOutChip=undefined\" , \"firstpartycookies_mmcore_srv\" : \"ldnvwcgus04\" , \"firstpartycookies_utag_ulog__ts\" : \"1434594193761\" , \"firstpartycookies_op_os\" : \"windows\" , \"firstpartycookies_mmcore_pd\" : \"-260045609|CgAAAAoBQo5qLK4SDC51it4BABwUz6WEd9JIDwAAAArc8xOEd9JIAAAAAP//////////ABF3d3cudHJlbmRtaWNyby5kZQMSDAEAAAAAAAAAAAAAM4IAAPB2AAAzggAAAQCqMwAAAFeiYjgSDAD/////ARIMEgz//wEAAAEAAAAAAZeDAADRzgAAAfB2AAABAAAAAAAAAUU=\" , \"firstpartycookies_utag_ulog__evc\" : \"9\" , \"firstpartycookies_channelflow\" : \"Other|other|1437186193989\" , \"firstpartycookies__mkto_trk\" : \"id:945-CXD-062&token:_mch-trendmicro-europe.com-1434593950434-55791\" , \"firstpartycookies_mm_orderid\" : \"13233624029\" , \"firstpartycookies_bigipserverp_gc2_prd_active_c020_m1\" : \"3979268106.260.0000\" , \"firstpartycookies_utag_main_v_id\" : \"014e047678c7001938f5bd7dcd6d0606d00a006500bd0\" , \"firstpartycookies_refurl\" : \"http://www.trendmicro.de/produkte/internet-sicherheitssoftware/index.html\" , \"firstpartycookies___utma\" : \"267052492.169290300.1434593950.1434593950.1434593950.1\" , \"firstpartycookies_fcpt\" : \"https://store.trendmicro-europe.com/DRHM/store\" , \"firstpartycookies___utmc\" : \"267052492\" , \"firstpartycookies_channeloriginator\" : \"Other\" , \"firstpartycookies___utmb\" : \"267052492.9.9.1434594128359\" , \"firstpartycookies_channelcloser\" : \"Other\" , \"firstpartycookies_utag_main__pn\" : \"5\" , \"firstpartycookies___utmz\" : \"267052492.1434593950.1.1.utmcsr=trendmicro.de|utmccn=(referral)|utmcmd=referral|utmcct=/produkte/internet-sicherheitssoftware/index.html\" , \"firstpartycookies___utmt\" : \"1\" , \"firstpartycookies_optimizelybuckets\" : \"{}\" , \"firstpartycookies_utag_ulog__sc\" : \"1\" , \"firstpartycookies_utag_ulog__ev\" : \"1\" , \"firstpartycookies_mmid\" : \"-1538482063|CgAAAAqOaiyuEgwAAA==\" , \"firstpartycookies_optimizelypendinglogevents\" : \"[\\\"n=https%3A%2F%2Fstore.trendmicro-europe.com%2Fstore%3FAction%3DDisplayPage%26Env%3DBASE%26Locale%3Dde_DE%26SiteID%3Dtmemea%26id%3DThankYouPage%26reqID%3D13233624029&u=oeu1434593947489r0.8301690202206373&wxhr=true&time=1434594193.487&f=2768980424,2971080012,2972670324,2977260584,2978640108,2979190277,2982862612,2996610471,2999320925,3002870234,3009590130,3010411532,3010490661,3012030325,3012290930,3013550107,3013760244,3015480251,3016230230,3016600354,3017680067,3018650199,3020070270,3021420266,3021900006,3022920263,3023490069,3023680079,3031860711,3035490758&g=2757770822,2786691329,2916450245\\\"]\" , \"firstpartycookies_tmemea_pgm\" : \"76176400\" , \"firstpartycookies_utag_ulog__ec\" : \"20\" , \"firstpartycookies_db_sampling_40\" : \"other\" , \"firstpartycookies_utag_ulog__vr\" : \"http://www.trendmicro.de/produkte/internet-sicherheitssoftware/index.html\" , \"firstpartycookies_mmcore_tst\" : \"0.143\" , \"firstpartycookies_optimizelysegments\" : \"{\\\"180328736\\\":\\\"gc\\\",\\\"180346625\\\":\\\"referral\\\",\\\"180346626\\\":\\\"false\\\",\\\"180356504\\\":\\\"none\\\",\\\"2368180888\\\":\\\"referral\\\",\\\"2368860567\\\":\\\"gc\\\",\\\"2386140173\\\":\\\"false\\\",\\\"2389240235\\\":\\\"none\\\"}\"}"; // 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/