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

/
/

Test String

Code Generator

Language

Generated Code

re = /(Policy Number:\s*)([A-Z0-9]+)(?=\s*Plan Eff\. Date:)/ str = 'OBX|1|FT|ED Fin||\\.br\\Butler Memorial Hospital Emergency Department\\.br\\\\.br\\One Hospital Way\\.br\\\\.br\\Butler, PA, 16001\\.br\\\\.br\\7242836666\\.br\\\\.br\\Patient: UPMC TEST DOB: 1/1/1945\\.br\\\\.br\\MR #: 200115 Age/Gender: 70y F\\.br\\\\.br\\DOS: 11/27/2015 08:15 Acct #: 20005591\\.br\\\\.br\\Private Phys: ED Phys:\\.br\\\\.br\\CHIEF COMPLAINT: Enc. Type: ACUITY:\\.br\\\\.br\\******** Initial Acuity unassigned\\.br\\\\.br\\Insurance\\.br\\\\.br\\1. Insurer Details\\.br\\\\.br\\Name: Relationship: SELF\\.br\\\\.br\\SSN: Employer Name:\\.br\\\\.br\\Sex:\\.br\\\\.br\\Insurance Type: UPMC HEALTH PLAN Plan Id: CPUPMC\\.br\\\\.br\\Policy Number: DKJSLFLSF Plan Eff. Date:\\.br\\\\.br\\Group Name: Group Number:\\.br\\\\.br\\Company Name: UPMC HEALTH PLAN Priority: 1\\.br\\\\.br\\Billing Status: Verify Indicator:\\.br\\\\.br\\TRIAGE\\.br\\\\.br\\Arrival: Patient arrived walking via car/private vehicle from home accompanied\\.br\\by parent(s) < KAL1 11/27/2015 08:24>\\.br\\\\.br\\Pain Level: Patient\'s pain is a 2 using a Wong-Baker scale. < KAL1 11/27/2015\\.br\\08:25>\\.br\\\\.br\\Patient not currently taking any medications.\\.br\\< KAL1 11/27/2015 08:25>\\.br\\\\.br\\Medical and surgical history obtained. <KAL1 11/27/15 08:25 >\\.br\\\\.br\\Patient states no travel to West Africa nor had contact with any person that\\.br\\has traveled to West Africa in the 21 days before illness onset. <KAL1\\.br\\11/27/2015 08:24>\\.br\\\\.br\\ALLERGIES\\.br\\\\.br\\+---------------------+--------------------+--------+------------------------+\\.br\\\\F\\Allergen \\F\\Status \\F\\Comments\\F\\Updated \\F\\\\.br\\\\F\\Reaction \\F\\ \\F\\ \\F\\ \\F\\\\.br\\+---------------------+--------------------+--------+------------------------+\\.br\\\\F\\*No Known Allergies* \\F\\Confirmed or \\F\\ \\F\\<KAL1 Nov 27 2015 \\F\\\\.br\\\\F\\ \\F\\verified \\F\\ \\F\\8:25AM> \\F\\\\.br\\+---------------------+--------------------+--------+------------------------+\\.br\\Patient not currently taking any medications.\\.br\\< KAL1 11/27/2015 08:25>\\.br\\\\.br\\HOME MEDICATIONS\\.br\\\\.br\\+-----------------------+----------+------+--------+-------------------------+\\.br\\\\F\\Medication Name \\F\\Last Dose \\F\\Status\\F\\Comments\\F\\Updated \\F\\\\.br\\\\F\\Instructions \\F\\Taken Date\\F\\ \\F\\ \\F\\ \\F\\\\.br\\+-----------------------+----------+------+--------+-------------------------+\\.br\\\\F\\*Not Taking Home Meds* \\F\\ \\F\\Active\\F\\ \\F\\<KAL1 Nov 27 2015 8:25AM>\\F\\\\.br\\+-----------------------+----------+------+--------+-------------------------+\\.br\\PAST MEDICAL / SURGICAL / SOCIAL HISTORY\\.br\\\\.br\\Smoking Status: Never smoked\\.br\\< KAL1 11/27/2015 08:25>\\.br\\\\.br\\No relevant surgeries.\\.br\\< KAL1 11/27/2015 08:26>\\.br\\\\.br\\DISPOSITION\\.br\\\\.br\\Nursing\\.br\\\\.br\\Disposition is Discharged - Routine\\.br\\< KAL1 11/27/2015 08:26>\\.br\\\\.br\\Family not notified of patient\'s disposition. <KAL1 11/27/15 08:26 >\\.br\\\\.br\\------------------------------------------------------------------------------\\.br\\\\.br\\Bed Assignments:\\.br\\\\.br\\MainWR INU 11/27/2015 08:15\\.br\\\\.br\\Status Activity:\\.br\\\\.br\\With Triage RN INU 11/27/2015 08:15\\.br\\\\.br\\Released KAL1 11/27/2015 08:28\\.br\\\\.br\\Acuity Activity:\\.br\\\\.br\\Acuity unassigned INU 11/27/2015 08:15\\.br\\\\.br\\Chart Documented By:\\.br\\\\.br\\KAL1: KALLIE TEST SIMMONS\\.br\\\\.br\\Release Information:\\.br\\\\.br\\Patient released 11/27/2015 08:28\\.br\\\\.br\\Released by KALLIE TEST SIMMONS\\.br\\\\.br\\Printed By User N. Interface on 11/27/2015 8:30 AM\\.br\\\\.br\\Medical Chart\\.br\\\\.br\\||||||S|' # Print the match result str.match(re) do |match| puts match.to_s end

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