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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
Processing...

Test String

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"coords.*\{[^}]+:.(\d+),[^}]+:.(\d*)\n.*}").unwrap(); let string = "{ \"name\": \"Medicare Annual Wellness Visit\", \"translate\": false, \"in_battery\": false, \"action\": \"submitTest.php\", \"conditionals_file\": \"conditionals-mwc.js\", \"alias\": \"MWC\", \"pdf_template\": \"annual_wellness_questionnaire.pdf\", \"info\": \"Please complete this checklist before seeing your doctor or nurse\", \"questions\": [ { \"title_eng\": \"What is your age?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"age\", \"is_last\": false, \"coords\": { \"y\": 112, \"x\": 38 } }, { \"title_eng\": \"Are you male or a female?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"gender\", \"is_last\": false, \"coords\": { \"y\": 121, \"x\": 38 } }, { \"title_eng\": \"During the past four weeks, has your physical and emotional health limited your social activities with family, friends and groups?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"state_slight\", \"is_last\": false, \"coords\": { \"y\": 140, \"x\": 38 } }, { \"title_eng\": \"During the past four weeks, how much body pain have you generally had?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"state_pain\", \"is_last\": false, \"coords\": { \"y\": 154, \"x\": 38 } }, { \"title_eng\": \"During the past four weeks, was someone available to help you if you wanted or needed help?<br/>(For example, if you felt very nervous, lonely or blue; got sick and had to stay in bed; needed someone to talk to; needed help with daily chores; or needed help just taking care of yourself.)\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"affirm_qty\", \"is_last\": false, \"coords\": { \"y\": 174, \"x\": 38 } }, { \"title_eng\": \"During the past four weeks, what was the hardest physical activity you could do for at least 2 minutes?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"state_grade\", \"is_last\": false, \"coords\": { \"y\": 194, \"x\": 38 } }, { \"title_eng\": \"Can you handle your own money without help?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean\", \"is_last\": false, \"coords\": { \"y\": 206, \"x\": 38 } }, { \"title_eng\": \"During the past four weeks, how would you rate your health in general?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"state_rate\", \"is_last\": false, \"coords\": { \"y\": 222.5, \"x\": 39 } }, { \"title_eng\": \"How have things been going for you in the past four weeks?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"life\", \"is_last\": false, \"coords\": { \"y\": 238, \"x\": 39 } }, { \"title_eng\": \"Are you having difficulties driving your car?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean_drive\", \"is_last\": false, \"coords\": { \"y\": 248, \"x\": 39 } }, { \"title_eng\": \"Do you always fasten your seat belt when you are in the car?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean_drive_b\", \"is_last\": false, \"coords\": { \"y\": 52, \"x\": 136 } }, { \"title_eng\": \"How often during the past four weeks have you been bothered by falling or dizziness when standing?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 87, \"x\": 173 } }, { \"title_eng\": \"How often during the past four weeks have you been bothered by sexual problems?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 94, \"x\": 173 } }, { \"title_eng\": \"How often during the past four weeks have you had trouble eating well?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 100, \"x\": 173 } }, { \"title_eng\": \"How often during the past four weeks have you been bothered by teeth or denture problems?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 105, \"x\": 173 } }, { \"title_eng\": \"How often during the past four weeks have you been bothered by problems using the telephone?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 112, \"x\": 173 } }, { \"title_eng\": \"How often during the past four weeks have you been bothered by tiredness or fatigue?\", \"title_esp\": \"\", \"scoring_method\": \"linear_gradation\", \"range_type\": \"state_freq\", \"is_last\": false, \"coords\": { \"y\": 117, \"x\": 173 } }, { \"title_eng\": \"Have you fallen 2 or more times during the past year?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean\", \"is_last\": false, \"coords\": { \"y\": 136, \"x\": 137 } }, { \"title_eng\": \"Are you afraid of falling?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean\", \"is_last\": false, \"coords\": { \"y\": 147, \"x\": 137 } }, { \"title_eng\": \"Are you a smoker?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean_smoker\", \"is_last\": false, \"coords\": { \"y\": 157, \"x\": 137 } }, { \"title_eng\": \"During the past four weeks, how many drinks of wine, beer or other alcoholic beverages did you have?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"freq_drinks\", \"is_last\": false, \"coords\": { \"y\": 176, \"x\": 137 } }, { \"title_eng\": \"Do you excercise for about 20 minutes three or more times a week?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"freq_exer\", \"is_last\": false, \"coords\": { \"y\": 190, \"x\": 137 } }, { \"title_eng\": \"Have you been given any information to help you with hazards in your home that may hurt you?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean\", \"is_last\": false, \"coords\": { \"y\": 204, \"x\": 187 } }, { \"title_eng\": \"Have you been given any information to help you with keeping track of your medications?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"boolean\", \"is_last\": false, \"coords\": { \"y\": 209, \"x\": 187 } }, { \"title_eng\": \"How often have you had trouble taking medications the way you are told to take them?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"freq_meds\", \"is_last\": false, \"coords\": { \"y\": 224, \"x\": 137 } }, { \"title_eng\": \"How confident are you that you can control and manage most of your health problems?\", \"title_esp\": \"\", \"scoring_method\": \"\", \"range_type\": \"state_confidence\", \"is_last\": false, \"coords\": { \"y\": 238, \"x\": 137 } }, { \"title_eng\": \"What is your race? (Check all that apply)\", \"title_esp\": \"\", \"scoring_method\": \"race\", \"range_type\": \"race\", \"is_last\": true, \"coords\": { \"y\": 243, \"x\": 137 } } ] }"; // 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/