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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(Policy Number:\s*)([A-Z0-9]+)(?=\s*Plan Eff\. Date:)`) var 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|` if len(re.FindStringIndex(str)) > 0 { fmt.Println(re.FindString(str),"found at index",re.FindStringIndex(str)[0]) } }

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 Golang, please visit: https://golang.org/pkg/regexp/