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

/
/
gm

Test String

Code Generator

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{1,}\[Documentation]\s*(.*)$|^\s{1,}\.{3}\s*(.*)$").unwrap(); let string = " ${DISPLAY_LINE1} 0 #TARIFF Display ${DISPLAY_LINE2} 1 #EXTRAS Display ${DISPLAY_LINE3} 2 #FARE Display @{TEST_SCREENS_WITH_TIMEOUT} ShowDesc ShowOsAndCountryCode ShowSW ShowSerial ... Checksum_PPSU Checksum_BPSU Checksum_LPSU Checksum_GPSU Checksum_AEPS Checksum_FEPS Checksum_GPAR ... Datetime_Clock Datetime_DDMM Datetime_Year ... ShowHWRevBaseboard ShowHWRevSOM Digio LVTL_Info ... TestMeasure_WDZ TestMeasure_SEC TestMeasure_MET TestMeasure_SPD @{TEST_SCREENS_WITHOUT_TIMEOUT} DisplayTest DisplaySettings Temperature @{CHECKSUM_SCREENS} Checksum_PPSU Checksum_BPSU Checksum_LPSU *** Keywords *** Program Version contain [Documentation] Read out program version and compare it with ${PROGARMM_VERSION} ... Comparison is done with \"Should Contain\" which is equal to Pythons \"in\" operator, ... it checks if ${PROGARMM_VERSION} is a substring of display content. ... Examples: Display content is \"P.ITM30\" ... Should Contain P.ITM30 ITM30 => PASS ... Should Contain P.ITM30 ITM => PASS ... Should Contain P.ITM30 I => PASS ... Should Contain P.ITM30 ITM40 => FAIL [Arguments] ${PROGARMM_VERSION} Fail if not on measure mode screen ShowOsAndCountryCode @{disp} = Read display in measure mode Should Contain @{disp}[${DISPLAY_LINE3}] ${PROGARMM_VERSION} Program version not found: ${PROGARMM_VERSION} Tarif EPS is [Documentation] Read out tarif EPS and compare it with ${TARIF_EPS} ... Comparison is done with \"Should be equal\" [Arguments] ${TARIF_EPS} Fail if not on measure mode screen Checksum_AEPS @{disp} = Read display in measure mode ${disp_traf_eps} = Catenate SEPARATOR= @{disp}[${DISPLAY_LINE1}] @{disp}[${DISPLAY_LINE3}] ${disp_traf_eps} = Replace String ${disp_traf_eps} . ${EMPTY} Should be equal ${disp_traf_eps} ${TARIF_EPS} Tarif EPS is not equal Release Date contain [Documentation] Read out program version and compare it with ${RELEASE_DATE} ... Comparison is done with \"Should Contain\" which is equal to Pythons \"in\" operator. ... For more information about the in-operator read Program Version contain - Keyword [Arguments] ${RELEASE_DATE} Fail if not on measure mode screen ShowSW @{disp} = Read display in measure mode Should Contain @{disp}[${DISPLAY_LINE3}] ${RELEASE_DATE} Release date not found: ${PROGRAM_VERSION} Checksum is not blinking [Documentation] Check if checksums displayed in MEASURE MODE does blinking [Arguments] ${CHECKSUM_SCREEN} Fail if not on measure mode screen ${CHECKSUM_SCREEN} "; // 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/