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

Code Generator

Language

Generated Code

// include the latest version of the regex crate in your Cargo.toml extern crate regex; use regex::Regex; fn main() { let regex = Regex::new(r#"(?m)^(<\!\-\- wp:onecms\/recipe-time \{\"type\"\:\"cook\")\S(.*[a-z\:0-9\}\s])(\/\-\->)$"#).unwrap(); let string = "<!-- wp:onecms/recipe-header {\"dek\":\"\\u003cp\\u003eHungry for some \\u003ca href=\\u0022https://www.southernliving.com/recipes/old-fashioned-apple-pie\\u0022\\u003eapple pie\\u003c/a\\u003e? We are right there with you. Here's the recipe from the Whispering Canyon Café at Disney’s Wilderness Lodge—dessert will never be the same.\\u003c/p\\u003e\"} /--> <!-- wp:onecms/primary-media /--> <!-- wp:onecms/recipe-media /--> <!-- wp:onecms/recipe-container --> <!-- wp:onecms/recipe-details --> <!-- wp:onecms/recipe-metadata {\"yieldDescription\":\"Makes one 9-inch pie.\"} /--> <!-- wp:onecms/recipe-times --> <!-- wp:onecms/recipe-time {\"type\":\"hands-on\",\"days\":0,\"hours\":0,\"minutes\":45} /--> <!-- wp:onecms/recipe-time {\"type\":\"cook\",\"days\":0,\"hours\":1,\"minutes\":0} /--> <!-- /wp:onecms/recipe-times --> <!-- /wp:onecms/recipe-details --> <!-- wp:onecms/recipe-ingredients --> <!-- wp:onecms/recipe-section-header {\"content\":\"Pie Crust\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"butter, cut into small pieces\",\"customMeasure\":\"tablespoons\",\"customQuantity\":\"4\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"shortening\",\"customMeasure\":\"cup\",\"customQuantity\":\"0.25\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"all-purpose flour\",\"customMeasure\":\"cups\",\"customQuantity\":\"1.75\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"sugar\",\"customMeasure\":\"teaspoons\",\"customQuantity\":\"4\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"coarse salt\",\"customMeasure\":\"teaspoon\",\"customQuantity\":\"0.13\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"2% milk\",\"customMeasure\":\"cup\",\"customQuantity\":\"0.33\"} /--> <!-- wp:onecms/recipe-section-header {\"content\":\"Apples\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"water\",\"customMeasure\":\"cup\",\"customQuantity\":\"1\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"Granny Smith apples, peeled and sliced\",\"customQuantity\":\"6\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"apple pie spice\",\"customMeasure\":\"teaspoon\",\"customQuantity\":\"2\"} /--> <!-- wp:onecms/recipe-section-header {\"content\":\"Apple Pie Batter\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"butter, softened\",\"customMeasure\":\"cup\",\"customQuantity\":\"0.5\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"sugar\",\"customMeasure\":\"cup\",\"customQuantity\":\"0.67\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"eggs\",\"customQuantity\":\"2\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"flour\",\"customMeasure\":\"cups\",\"customQuantity\":\"1.5\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"baking powder\",\"customMeasure\":\"teaspoon\",\"customQuantity\":\"1.5\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"salt\",\"customMeasure\":\"teaspoon\",\"customQuantity\":\"0.13\"} /--> <!-- wp:onecms/recipe-ingredient-custom {\"customIngredient\":\"heavy cream\",\"customMeasure\":\"cup\",\"customQuantity\":\"0.25\"} /--> <!-- /wp:onecms/recipe-ingredients --> <!-- wp:onecms/recipe-nutrition {\"displayNutritionRecipe\":false} /--> <!-- wp:onecms/recipe-directions --> <!-- wp:onecms/recipe-direction {\"directionId\":\"ddaa1eec-7bec-4284-b4e3-53b35cb83941\",\"content\":\"\\u003cstrong\\u003eFOR PIE CRUST: \\u003c/strong\\u003e\"} /--> <!-- wp:onecms/recipe-direction {\"directionId\":\"e546e3c3-96a5-4be5-94fa-34ee625f3a48\",\"content\":\"\\u003cstrong\\u003eFOR APPLES:\\u003c/strong\\u003e\"} /--> <!-- wp:onecms/recipe-direction {\"directionId\":\"49fbc0c6-12f0-420c-9dc6-19210620e023\",\"content\":\"\\u003cstrong\\u003eFOR APPLE PIE BATTER:\\u003c/strong\\u003e\"} /--> <!-- wp:onecms/recipe-direction {\"directionId\":\"208717df-e3e3-43e9-a2bc-35ad854ae43c\",\"content\":\"\\u003cstrong\\u003eFOR APPLE PIE:\\u003c/strong\\u003e\"} /--> <!-- /wp:onecms/recipe-directions --> <!-- wp:onecms/recipe-notes --> <!-- wp:onecms/recipe-note /--> <!-- /wp:onecms/recipe-notes --> <!-- /wp:onecms/recipe-container -->"; // result will be an iterator over tuples containing the start and end indices for each match in the string let result = regex.captures_iter(string); for mat in result { println!("{:?}", mat); } }

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 Rust, please visit: https://docs.rs/regex/latest/regex/