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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?m)^Ingredients\R((?>(?!Ingredients$).*\R)+?)Preparation$") test_str = ("Recipes & Menus\n" "Expert Advice\n" "Ingredients\n" "Holidays & Events\n" "Community\n" "Video\n" "SUMMER COOKING\n" "Lentil and Brown Rice Soup\n" "Gourmet January 1991\n" "3.5/4\n" "reviews (83)\n" "90%\n" "make it again\n" "Some soups genuinely do inspire a devotion akin to love, and this is one of\n" "them. In the cold of winter, when Gourmet editors ponder the matter of what soup\n" "Cook\n" "Reviews (83)\n" "YIELD: Makes about 14 cups, serving 6 to 8\n" "Ingredients\n" "5 cups chicken broth\n" "1 1/2 cups lentils, picked over and rinsed\n" "1 cup brown rice\n" "a 32- to 35-ounce can tomatoes, drained, reserving the juice, and chopped\n" "3 carrots, halved lengthwise and cut crosswise into 1/4-inch pieces\n" "1 onion, chopped\n" "1 stalk of celery, chopped\n" "3 garlic cloves, minced\n" "1/2 teaspoon crumbled dried basil\n" "1/2 teaspoon crumbled dried orégano\n" "1/4 teaspoon crumbled dried thyme\n" "1 bay leaf\n" "1/2 cup minced fresh parsley leaves\n" "2 tablespoons cider vinegar, or to taste\n" "Preparation\n" "In a heavy kettle combine the broth, 3 cups water, the lentils, the rice, the tomatoes with the reserved juice,") match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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