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

re = /0x[0-9a-fA-F]{8}[\t ]*(\S+)/m str = '/ 260: fcn.004020b0 (int32_t arg_4h, int32_t arg_8h); | ; var int32_t var_324h @ ebp-0x324 | ; arg int32_t arg_4h @ ebp+0x4 | ; arg int32_t arg_8h @ ebp+0x8 | 0x004020b0 55 push ebp | 0x004020b1 8bec mov ebp, esp | 0x004020b3 81ec24030000 sub esp, 0x324 | 0x004020b9 6a17 push 0x17 ; 23 | 0x004020bb ff151c304000 call dword [sym.imp.KERNEL32.dll_IsProcessorFeaturePresent] ; 0x40301c | 0x004020c1 85c0 test eax, eax | ,=< 0x004020c3 7407 je 0x4020cc | | 0x004020c5 b902000000 mov ecx, 2 | | 0x004020ca cd29 int 0x29 | | ; CODE XREF from fcn.004020b0 @ 0x4020c3 | `-> 0x004020cc a340744000 mov dword [0x407440], eax ; [0x407440:4]=0 | 0x004020d1 890d3c744000 mov dword [0x40743c], ecx ; [0x40743c:4]=0 | 0x004020d7 891538744000 mov dword [0x407438], edx ; [0x407438:4]=0' # Print the match result str.scan(re) do |match| puts match.to_s end

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html