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

package main import ( "regexp" "fmt" ) func main() { var re = regexp.MustCompile(`(?m)(?si)m_dwErrorCode\s*=\s*(?<code>\dx\d+);\s*_stprintf\(.*?\(.*?\((?<description>.*?)\).*?;\s*m_dwOutError\s*=\s*(?<error>[\w_]+);\s*m_OutSeverity\s*=\s*(?<severity>[\w_]+)`) var str = `m_dwErrorCode = 0; m_dwOutError = HOP_OK; m_OutSeverity = CCC_INFORMATION; _stprintf(m_OutDevStr, _T("")); if (0x00000000 & value) { m_dwErrorCode = 0x0; /* Ready state. */ // m_StatusStr = " Ready(eSTATUS_READY)"; } if (0x00000001 & value) { m_bProceeding = true; /* proceed */ //m_StatusStr = " Proceeding(eSTATUS)"; } if (0x00002000 & value) { m_bEmpty = true; // We only want to check this error only at certain times. if (m_bCheckEmpty) { if ((m_Attributes.dwMediaID == CUBE1) || (m_Attributes.dwMediaID == CUBE2) || /*(m_Attributes.dwMediaID == SCALLOPED) ||*/ // Added (m_Attributes.dwMediaID == FOLDED)) { m_dwErrorCode = 0x00002000; _stprintf(m_OutDevStr, _T("0x1000 - %s(MP Tray Empty)"), errorStr); m_dwOutError = HOP_TRAY_EMPTY; m_OutSeverity = CCC_INFORMATION; } } //HOP_TRAY_EMPTY ///* MSI empty. */ //m_bTrayEmpty = true; //// m_StatusStr = " MSI empty(eSTATUS_MSI_EMPTY)"; } if (0x00004000 & value) { /* empty. */ m_dwErrorCode = 0x4000; _stprintf(m_OutDevStr, _T("0x4000 - %s(Tray 1 empty)"), errorStr); m_dwOutError = HOP_TRAY_01_EMPTY; m_OutSeverity = CCC_INFORMATION; } if (0x00008000 & value) { /* Tray 2 empty. */ m_dwErrorCode = 0x8000; _stprintf(m_OutDevStr, _T("0x8000 - %s(Tray 2 empty)"), errorStr); m_dwOutError = HOP_TRAY_02_EMPTY; m_OutSeverity = CCC_INFORMATION; } if (0x00010000 & value) { /* Tray 3 empty. */ m_dwErrorCode = 0x10000; _stprintf(m_OutDevStr, _T("0x10000 - %s(Tray 3 empty)"), errorStr); m_dwOutError = HOP_TRAY_03_EMPTY; m_OutSeverity = CCC_INFORMATION; }` for i, match := range re.FindAllString(str, -1) { fmt.Println(match, "found at index", i) } }

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 Golang, please visit: https://golang.org/pkg/regexp/