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

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"^(?'id'[0-9a-fA-F]{2})(?:-(?'id_to'\w+))? ([ \/\w-]+)(?: [\/\w]+ \d+\.\d+)?$" test_str = ("00 Undefined\n" "01 Flight Simulation Device CA 5.2\n" "02 Automobile Simulation Device CA 5.3\n" "03 Tank Simulation Device CA 5.4\n" "04 Spaceship Simulation Device CA 5.2\n" "05 Submarine Simulation Device CA 5.5\n" "06 Sailing Simulation Device CA 5.5\n" "07 Motorcycle Simulation Device CA 5.6\n" "08 Sports Simulation Device CA 5.1\n" "09 Airplane Simulation Device CA 5.2\n" "0A Helicopter Simulation Device CA 5.2\n" "0B Magic Carpet Simulation Device CA 5.7\n" "0C Bicycle Simulation Device CA 5.6\n" "0D-1F Reserved\n" "20 Flight Control Stick CA 5.2\n" "21 Flight Stick CA 5.2\n" "22 Cyclic Control CP 5.2\n" "23 Cyclic Trim CP 5.2\n" "24 Flight Yoke CA 5.2\n" "25 Track Control CP 5.4\n" "26-AF Reserved\n" "B0 Aileron DV 5.2\n" "B1 Aileron Trim DV 5.2\n" "B2 Anti-Torque Control DV 5.2\n" "B3 Autopilot Enable OOC 5.2\n" "B4 Chaff Release OSC 5.2\n" "B5 Collective Control DV 5.2\n" "B6 Dive Brake DV 5.2\n" "B7 Electronic Countermeasures OOC 5.2\n" "B8 Elevator DV 5.2\n" "B9 Elevator Trim DV 5.2\n" "BA Rudder DV 5.2\n" "BB Throttle DV 5.2\n" "BC Flight Communications OOC 5.2\n" "BD Flare Release OSC 5.2\n" "BE Landing Gear OOC 5.2\n" "BF Toe Brake DV 5.2\n" "C0 Trigger MC 5.2\n" "C1 Weapons Arm OOC 5.2\n" "C2 Weapons Select OSC 5.2\n" "54\n" "C3 Wing Flaps DV 5.2\n" "C4 Accelerator DV 5.3\n" "C5 Brake DV 5.3\n" "C6 Clutch DV 5.3\n" "C7 Shifter DV 5.3\n" "C8 Steering DV 5.3\n" "C9 Turret Direction DV 5.4\n" "CA Barrel Elevation DV 5.4\n" "CB Dive Plane DV 5.5\n" "CC Ballast DV 5.5\n" "CD Bicycle Crank DV 5.6\n" "CE Handle Bars DV 5.6\n" "CF Front Brake DV 5.6\n" "D0 Rear Brake DV 5.6\n" "D1-FFFF Reserved\n") subst = "\\t${id_to:+// 0x${id}-0x${id_to} $3:${name} = 0x${id},}" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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 Python, please visit: https://docs.python.org/3/library/re.html