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)([^\|\s]\s*\[x\]\s*\K[^!|\n]*|(?:\G(?!\A)\||(?<=\[x]\s)\s*\|)\K[^|\n]*(?=\|))|([^\|\s]\s*\[x\]\s*\!\s*\K[^|\n]*|(?:\G(?!\A)\||(?<=\[x]\s)\s*\!\s*\|)\K[^|\n]*(?=\|))").unwrap(); let string = "Text for testing: - [x] Example task. | Task ends. [x] Another task. - [x] ! Example task. | This ends. [x] ! Another task. This is a sentence. [x] Task is here. Other text. Another [x] ! Task is here. | | Task name | Plan | Actual | File | | :---- | :-------------| :---------: | :---------: | :------------: | | [x] | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] | | [x] ! | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] | Description: - $1: - outside the table: capture everything after `[x]` (i.e., not followed by `!`) until a `|` - inside the table: capture everything after `[x]` (i.e., not followed by `!`) excluding the `|` symbols - $2: - outside the table: capture everything after `[x] !` until a `|` - inside the table: capture everything after `[x] !` excluding the `|` symbols Expressions for each group: - $1: - outside the table: [^\\|\\s]\\s*\\[x\\]\\s*\\K[^!|\\n]* - inside the table: (?:\\G(?!\\A)\\||(?<=\\[x]\\s)\\s*\\|)\\K[^|\\n]*(?=\\|) - $2: - outside the table: [^\\|\\s]\\s*\\[x\\]\\s*\\!\\s*\\K[^|\\n]* - inside the table: (?:\\G(?!\\A)\\||(?<=\\[x]\\s)\\s*\\!\\s*\\|)\\K[^|\\n]*(?=\\|) Combined expression: ([^\\|\\s]\\s*\\[x\\]\\s*\\K[^!|\\n]*|(?:\\G(?!\\A)\\||(?<=\\[x]\\s)\\s*\\|)\\K[^|\\n]*(?=\\|))|([^\\|\\s]\\s*\\[x\\]\\s*\\!\\s*\\K[^|\\n]*|(?:\\G(?!\\A)\\||(?<=\\[x]\\s)\\s*\\!\\s*\\|)\\K[^|\\n]*(?=\\|)) "; // 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/