Regular Expressions 101

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Community Patterns

1

All zeros after first digit

ECMAScript (JavaScript)
Number string where only zeros follow the first digit
Submitted by anonymous - 22 days ago
1

Multiple Severity-Diagnostic Related Groups (MS-DRGs)

PCRE2 (PHP >=7.3)
Multiple Severity-Diagnostic Related Groups (MS-DRGs)
Submitted by john (jacko) logan - 23 days ago
1

Multiple Severity-Diagnostic Related Groups (MS-DRGs)

PCRE2 (PHP >=7.3)
Multiple Severity-Diagnostic Related Groups (MS-DRGs)
Submitted by anonymous - 23 days ago
1

FL 16 - Discharge Hour FL 17 - Patient Discharge Status

PCRE2 (PHP >=7.3)
FL 16 - Discharge Hour FL 17 - Patient Discharge Status
Submitted by John (Jacko) Logan - 23 days ago
1

Current Procedural Terminology (CPT) codes, incl optional modifiers

PCRE2 (PHP >=7.3)
CPT is a uniform coding system consisting of descriptive terms and identifying codes used primarily to identify medical services and procedures furnished by physicians and other health care professionals for which they bill public or private health insurance programs. It is a numeric coding system ...
Submitted by Richard Baxter - 23 days ago (Last modified 23 days ago)
1

Current Procedural Terminology (CPT) codes

PCRE2 (PHP >=7.3)
CPT is a uniform coding system consisting of descriptive terms and identifying codes used primarily to identify medical services and procedures furnished by physicians and other health care professionals for which they bill public or private health insurance programs. It is a numeric coding system ...
Submitted by Richard Baxter - 23 days ago (Last modified 23 days ago)
1

'Type of Bill' / 'Bill Type' FL4 (US Healthcare Billing Codes)

PCRE2 (PHP >=7.3)
Used to identify the patient's care during their hospital stay and help ensure that hospitals are reimbursed accurately for their services. A data element corresponding with UB-04 form locator FL4 that classifies the claim as to the type of facility (2nd digit), type of care (3rd digit) and the bil...
Submitted by Richard Baxter - 23 days ago (Last modified 21 days ago)
1

Revenue Codes (Billing in US Healthcare)

PCRE2 (PHP >=7.3)
Revenue codes are standardized numerical codes used in the healthcare industry to specify the type of service provided by healthcare facilities on patient billing statements. They help categorize and detail the services rendered for both inpatients and outpatients, allowing for accurate billing and ...
Submitted by Richard Baxter - 23 days ago
1

HCPCS Level II codes (and modifier)

ECMAScript (JavaScript)
The CMS, who maintain these codes, describe the format as:- "HCPCS Level II codes (also known as alpha-numeric codes) consist of a single alphabetical letter followed by 4 numeric digits." (https://www.cms.gov/medicare/coding-billing/healthcare-common-procedure-system) NOTE: This regex will not ide...
Submitted by Richard Baxter - 23 days ago
1

HCPCS Level II codes (no modifier)

ECMAScript (JavaScript)
The CMS, who maintain these codes, describe the format as:- "HCPCS Level II codes (also known as alpha-numeric codes) consist of a single alphabetical letter followed by 4 numeric digits." (https://www.cms.gov/medicare/coding-billing/healthcare-common-procedure-system) NOTE: This regex will not iden...
Submitted by Richard Baxter - 23 days ago
1

Place of Service [POS] Codes

PCRE2 (PHP >=7.3)
These codes are used to indicate where a medical service was provided in US healthcare (https://www.cms.gov/medicare/coding-billing/place-of-service-codes/code-sets). The codes should be 2 digits. Single digits should have a leading 0. It's possible data loading might drop such values, and then t...
Submitted by Richard Baxter - 23 days ago
1

LOINC Medical Codes (from LOINC.org)

PCRE2 (PHP >=7.3)
Pattern to identify LOINC codes, derived from the description in LOINC.org (June 2024):- LOINC codes have a fixed length field of 7 characters within the LOINC database. Current codes are from 3-7 characters long. If you are currently building a system to include LOINC codes, we advise allowing up t...
Submitted by Richard Baxter - 23 days ago
1

x86 ASM Register [Case-Insensitive]

PCRE2 (PHP >=7.3)
A RegEx to match any Intel x86-Assembly register in a case-insensitive way. This is due to a limitation of the engine this regular expression was originally written for. Here is an updated version that is written for Regex-Engines that support the /i flag: https://regex101.com/library/4v1bVf
Submitted by Tim Clemens - 24 days ago
1

x86 ASM Register

PCRE2 (PHP >=7.3)
A RegEx to match any Intel x86-Assembly register.
Submitted by Tim Clemens - 24 days ago
1

chicken bacon onion

PCRE2 (PHP >=7.3)
for find chicken bacon onion
Submitted by ZXC_SaxarokUWU_ZXC - 24 days ago
1

Validation - HTTP User Agent

PCRE2 (PHP >=7.3)
Validate only / non-capturing
Submitted by razor velvet - 25 days ago
1

RFC5322 email address validation (maybe FEWER STEPS !)

PCRE2 (PHP >=7.3)
validate email address according to RFC 5322 specification. I tried to optimize regex radically restructuring the original BNF-like specification with full support preserved.
Submitted by hirunotuki - a month ago
2

Test 1 solution

PCRE2 (PHP >=7.3)
thanks
Submitted by Zeeble Dorp - a month ago
1

Postcode validation

PCRE2 (PHP >=7.3)
I come across Dutch postcodes quite different from normal 5 or 6 digit postcodes. So, this regex covers most possible postcodes. Test cases: 1234 AB // Dutch postal code 12345 // Generic 5-digit postal code 380059 // Indian 6-digit postal code...
Submitted by Pratik P - a month ago
1

match all test directories

PCRE2 (PHP >=7.3)
s
Submitted by anonymous - a month ago
12345...299

RFC5322 email address validation (maybe FEWER STEPS !)

1

Regular Expression
PCRE2 (PHP >=7.3)

/
^(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+(?>(?>[\w\d!#-'*+\/=?^`{-~-]++|(?>"(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!#-\[\]-\x7f]++|\\[\x00-\x7f]))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+"))(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+(?>\.(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+(?>[\w\d!#-'*+\/=?^`{-~-]++|(?>"(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!#-\[\]-\x7f]++|\\[\x00-\x7f]))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+"))(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+)*+)@(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+(?>[\w\d!#-'*+\/=?^`{-~-]++(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+(?>\.(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+[\w\d!#-'*+\/=?^`{-~-]++(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+)*+|\[(?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-Z^-\x7f]++|\\[\x00-\x7f]))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\](?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>(?>(\((?>(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+(?>[\x01-\x08\x0b\x0c\x0e-\x1f!-'*-\[\]-\x7f]++|\\[\x00-\x7f]|(?-1)))*+(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+\))(?>[ \t]++(?>\r\n[ \t]++)*+|\r\n[ \t]++)?+)++)?+)?+)$
/
gm
Open regex in editor

Description

validate email address according to RFC 5322 specification. I tried to optimize regex radically restructuring the original BNF-like specification with full support preserved.

Submitted by hirunotuki - a month ago