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"
"
gms

Test String

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"^([a-zA-Z]+)\s*\{(.*?)}(?=\n[a-zA-Z]+\s*{\n|\Z)" test_str = ("BackdropNode {\n" " inputs 0\n" " name BackdropNode6\n" " tile_color 0x555555ff\n" " label RDN\n" " note_font_size 42\n" " xpos -1136\n" " ypos -4272\n" " bdwidth 451\n" " bdheight 529\n" "}\n" "Write {\n" " file \"\\[value project_directory]/_output_/\\[string range \\[file tail \\[value root.name]] 0 20].mov\"\n" " colorspace sRGB\n" " raw true\n" " file_type mov\\{(.*?)\\}\n" " mov64_format \"mov (QuickTime / MOV)\"\n" " mov64_codec AVdh\n" " mov64_dnxhd_codec_profile \"DNxHD 422 8-bit 145Mbit\"\n" " mov64_dnxhr_codec_profile \"SQ 4:2:2 8-bit\"\n" " mov64_pixel_format {{0} \"yuv420p\\tYCbCr 4:2:0 8-bit\"}\n" " mov64_quality High\n" " mov64_advanced 1\n" " mov64_write_timecode true\n" " mov64_gop_size 12\n" " mov64_b_frames 0\n" " mov64_bitrate 20000\n" " mov64_bitrate_tolerance 40000000\n" " mov64_quality_min 2\n" " mov64_quality_max 31\n" " render_order 3\n" " checkHashOnRead false\n" " version 132\n" " in_colorspace scene_linear\n" " out_colorspace scene_linear\n" " name Write2\n" " xpos -1025\n" " ypos 2230\n" "}") matches = re.finditer(regex, test_str, re.MULTILINE | re.DOTALL) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # 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