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

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"(餐盘|餐具|餐盒)收(一下|下|掉)?|收(一下|下)?(餐盘|餐具|餐盒|餐)" test_str = ("收一下餐。\n" "吗，我总是吗个服务员帮我收下餐盘。\n" "收一下餐。\n" "收餐？\n" "帮我叫个服务员收一下餐盘。\n" "嗯，收一下餐具。\n" "收一下餐。\n" "就是麻烦你收费早餐算呢？\n" "收一下餐。\n" "帮我收一下餐盘。\n" "帮我收一下餐盘。\n" "嗯，帮我收回去好吗？我这个用餐有用完了。\n" "收餐？\n" "请帮我收一下餐盘。\n\n" "收一下餐。\n" "吗，我总是吗个服务员帮我收下餐盘。\n" "收一下餐。\n" "我刚刚有一份那个中餐收到了，没有？\n" "早餐九点半收。\n" "收餐？\n" "帮我叫个服务员收一下餐盘。\n" "嗯，收一下餐具。\n" "收一下餐。\n" "就是麻烦你收费早餐算呢？\n" "收一下餐。\n" "帮我收一下餐盘。\n" "帮我收一下餐盘。\n" "早餐收钱吗？\n" "嗯，帮我收回去好吗？我这个用餐有用完了。\n" "把那个餐具收掉。\n" "帮我把餐盒拿收拾下房间。\n" "收餐？\n" "请帮我收一下餐盘。") matches = re.finditer(regex, test_str, re.MULTILINE) 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