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

r"
"
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

import Foundation let pattern = #"(?:\s*?NAME\s*?:\s*?\"?)([0-9A-Za-z- ,]+)(?:\"?\s*?,\s*?)(?:DESCR\s*?:\s*\"?)([0-9A-Za-z- ,/+:]+)(?:\"?\s*?PID\s*?:\s*?)([0-9A-Z-]+)(?:\s*?,\s*?VID\s*?:\s*?)([0-9A-Z/]+)(?:\s*?,\s*?SN\s*?:\s*?)([0-9A-Z/]+)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" NAME: "Chassis", DESCR: "Nexus C9348GC-FXP chassis" PID: N9K-C9348GC-FXP , VID: V01 , SN: FFFFFFFFFFF NAME: "Slot 1 ", DESCR: "48x100M/1G " PID: N9K-C9348GC-FXP , VID: V01 , SN: FFFFFFFFFFF NAME: "GEM ", DESCR: "4x25G+2x100G Switch " PID: N9K-C9348GC-FXP , VID: V01 , SN: FFFFFFFFFFF NAME: "power Supply 1", DESCR: "PSU " PID: NXA-PAC-350W-PE , VID: V01 , SN: DDDDDDDDDDD NAME: "power Supply 2", DESCR: "PSU " PID: NXA-PAC-350W-PE , VID: V01 , SN: DDDDDDDDDDD NAME: "Fan 1 ", DESCR: "fan " PID: NXA-FAN-30CFM-F , VID: N/A , SN: N/A NAME: "Fan 2 ", DESCR: "fan " PID: NXA-FAN-30CFM-F , VID: N/A , SN: N/A NAME: "Fan 3 ", DESCR: "fan " PID: NXA-FAN-30CFM-F , VID: N/A , SN: N/A """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let substitutionString = #""# let result = regex.stringByReplacingMatches(in: testString, range: stringRange, withTemplate: substitutionString) print(result)

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression