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

/
/
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"\s+(?P<tst_dvc>[^\s]+)\s+\w{3}\s+\d{1,2}\s+\d{2}\:\d{2}\:\d{2}\s(?P<tst_cmd>[^:]+):\s+(?P<tst_action>[^\s]+)\s+<\d>(?P<tst_action2>[^\s]+)\s+IN=(?P<tst_in_if>[^\s]+)\s+OUT=(?P<tst_out_if>[^\s]+)\s+<\d>(?P<tst_src_ip>[^\s]+)\s+DST=(?P<tst_dest_ip>[^\s]+)\s+<\d>LEN=(?P<tst_len>[^\s]+)\s+TOS=(?P<tst_tos>[^\s]+)\s+PREC=(?P<tst_prec>[^\s]+)\s+TTL=(?P<tst_ttl>[^\s]+)\s+ID=(?P<tst_id>[^\s]+)\s+(DF\s+|\s+)PROTO=(?P<tst_proto>[^\s]+)\s+<\d>SPT=(?P<tst_src_port>[^\s]+)\s+DPT=(?P<tst_dest_port>[^\s]+)\s+"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" Sep 10 20:18:17 gateway.3deep.local Sep 10 20:18:17 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=54.208.123.145 DST=192.168.23.50 <1>LEN=60 TOS=0x00 PREC=0x00 TTL=37 ID=28012 DF PROTO=TCP <1>SPT=38859 DPT=443 SEQ=636829265 ACK=0 WINDOW=17922 RES=0x00 SYN URGP=0 OPT (020405AC0402080ABDC6533D0000000001030304) Sep 9 00:44:27 gateway.3deep.local Sep 9 00:44:27 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=110.167.234.34 DST=192.168.23.50 <1>LEN=48 TOS=0x00 PREC=0x00 TTL=108 ID=3857 DF PROTO=TCP <1>SPT=26932 DPT=443 SEQ=1819196068 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405AC01010402) Sep 8 22:51:18 gateway.3deep.local Sep 8 22:51:17 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=110.167.234.34 DST=192.168.23.50 <1>LEN=44 TOS=0x00 PREC=0x00 TTL=100 ID=256 PROTO=TCP <1>SPT=12589 DPT=443 SEQ=597164032 ACK=0 WINDOW=16384 RES=0x00 SYN URGP=0 OPT (020405AC) Sep 7 02:28:36 gateway.3deep.local Sep 7 02:28:22 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=40 TOS=0x00 PREC=0x00 TTL=247 ID=40368 DF PROTO=TCP <1>SPT=7004 DPT=443 SEQ=1635675828 ACK=2838771327 WINDOW=1024 RES=0x00 ACK URGP=0 Sep 7 01:36:17 gateway.3deep.local Sep 7 01:36:03 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=52 TOS=0x08 PREC=0x00 TTL=54 ID=1014 DF PROTO=TCP <1>SPT=32594 DPT=443 SEQ=3142748749 ACK=3448075871 WINDOW=863 RES=0x00 ACK RST URGP=0 OPT (0101080A00E4FAF60079E548) Sep 7 01:36:17 gateway.3deep.local Sep 7 01:36:03 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=83 TOS=0x08 PREC=0x00 TTL=54 ID=1013 DF PROTO=TCP <1>SPT=32594 DPT=443 SEQ=3142748718 ACK=3448075871 WINDOW=863 RES=0x00 ACK PSH URGP=0 OPT (0101080A00E4FAF50079E548) Sep 7 01:35:38 gateway.3deep.local Sep 7 01:35:24 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=83 TOS=0x08 PREC=0x00 TTL=54 ID=11557 DF PROTO=TCP <1>SPT=5010 DPT=443 SEQ=3044040977 ACK=3364857459 WINDOW=841 RES=0x00 ACK PSH URGP=0 OPT (0101080A00E4ECD6007955EC) Sep 7 01:35:19 gateway.3deep.local Sep 7 01:35:05 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=52 TOS=0x08 PREC=0x00 TTL=54 ID=23094 DF PROTO=TCP <1>SPT=21273 DPT=443 SEQ=1560229817 ACK=221451921 WINDOW=995 RES=0x00 ACK RST URGP=0 OPT (0101080A00E4E5BE00790C82) Sep 7 01:35:19 gateway.3deep.local Sep 7 01:35:05 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=83 TOS=0x08 PREC=0x00 TTL=54 ID=23093 DF PROTO=TCP <1>SPT=21273 DPT=443 SEQ=1560229786 ACK=221451921 WINDOW=995 RES=0x00 ACK PSH URGP=0 OPT (0101080A00E4E5BE00790C82) Sep 7 01:35:17 gateway.3deep.local Sep 7 01:35:03 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=83 TOS=0x08 PREC=0x00 TTL=54 ID=27577 DF PROTO=TCP <1>SPT=7678 DPT=443 SEQ=3690596392 ACK=1344433672 WINDOW=1017 RES=0x00 ACK PSH URGP=0 OPT (0101080A00E4E50000790783) Sep 7 01:31:00 gateway.3deep.local Sep 7 01:30:45 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=60856 DF PROTO=TCP <1>SPT=7004 DPT=443 SEQ=1635675080 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E486700000000001030307) Sep 7 01:30:58 gateway.3deep.local Sep 7 01:30:44 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=52 TOS=0x08 PREC=0x00 TTL=54 ID=65096 DF PROTO=TCP <1>SPT=40737 DPT=443 SEQ=3785465976 ACK=3145025690 WINDOW=797 RES=0x00 ACK RST URGP=0 OPT (0101080A00E485C500786FF0) Sep 7 01:30:58 gateway.3deep.local Sep 7 01:30:44 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=83 TOS=0x08 PREC=0x00 TTL=54 ID=65095 DF PROTO=TCP <1>SPT=40737 DPT=443 SEQ=3785465945 ACK=3145025690 WINDOW=797 RES=0x00 ACK PSH URGP=0 OPT (0101080A00E485C500786FF0) Sep 7 01:30:55 gateway.3deep.local Sep 7 01:30:41 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=36669 DF PROTO=TCP <1>SPT=17827 DPT=443 SEQ=2974944174 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E484930000000001030307) Sep 7 01:30:55 gateway.3deep.local Sep 7 01:30:40 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=1001 DF PROTO=TCP <1>SPT=32594 DPT=443 SEQ=3142748053 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E4847C0000000001030307) Sep 7 01:30:18 gateway.3deep.local Sep 7 01:30:04 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=12619 DF PROTO=TCP <1>SPT=21832 DPT=443 SEQ=1570588497 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E4761A0000000001030307) Sep 7 01:30:11 gateway.3deep.local Sep 7 01:29:57 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=45093 DF PROTO=TCP <1>SPT=21730 DPT=443 SEQ=2658911151 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E4738A0000000001030307) Sep 7 01:30:11 gateway.3deep.local Sep 7 01:29:57 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=11542 DF PROTO=TCP <1>SPT=5010 DPT=443 SEQ=3044040312 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E4736E0000000001030307) Sep 7 01:30:04 gateway.3deep.local Sep 7 01:29:50 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=60 TOS=0x08 PREC=0x00 TTL=54 ID=20511 DF PROTO=TCP <1>SPT=58071 DPT=443 SEQ=2243567858 ACK=0 WINDOW=65535 RES=0x00 SYN URGP=0 OPT (020405780402080A00E470ED0000000001030307) Sep 7 01:30:04 gateway.3deep.local Sep 7 01:29:50 kernel: ACCEPT <4>ACCEPT IN=ppp0 OUT=br0 <1>SRC=1.144.97.10 DST=192.168.23.50 <1>LEN=52 TOS=0x08 PREC=0x00 TTL=54 ID=24652 DF PROTO=TCP <1>SPT=13328 DPT=443 SEQ=293238401 ACK=1045411505 WINDOW=12277 RES=0x00 ACK RST URGP=0 OPT (0101080A00E4708E0076D730) """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } 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