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

import re regex = re.compile(r""" [*][(][\s]*[(\s]*.*[*][)\s]*(.*)\s*[)]\s*=(.*)[\s]*; """, flags=re.IGNORECASE | re.VERBOSE) test_str = (" (*((volatile unsigned short*)(type01_01_06_base + (type01_01_06_offset * 1))) = (unsigned short)(unsigned long)0x01010101);\n" " (*((volatile unsigned short*)(type01_01_06_base + (type01_01_06_offset * 2))) = (unsigned short)(unsigned long)0x01000100);\n\n" "(*((volatile unsigned char*)add)) = (unsigned char)data;\n\n" "(*((volatile unsigned short*)add)) = (unsigned short)data;\n\n" "(*((volatile unsigned long*)add)) = (unsigned long)data;\n\n\n" " \n" " *((volatile unsigned char*)0x01010004) = (unsigned char)0x01;\n" " *((volatile unsigned char*)0x01010008) = (unsigned char)0x00;\n\n" " *((volatile unsigned short*)0x01020004) = (unsigned short)0x0100;\n" " *((volatile unsigned short*)0x01020008) = (unsigned short)0x0000;\n\n" " *((volatile unsigned long*)(0x01030000 + 0x04)) = (unsigned long)0x00010000;\n" " *((volatile unsigned long*)(0x01030000 + 0x08)) = (unsigned long)0x00000000;\n\n" " (*((volatile unsigned char*)type01_01_04o_add) = (unsigned char)(unsigned char)0xA5);\n\n" " (*((volatile unsigned char*)type01_01_04n_add) = (unsigned char)(unsigned char)0x5A);\n\n" " (*((volatile unsigned short*)(type01_01_05_base + type01_01_05o_offset)) = (unsigned short)(unsigned short)0x0101);\n" " (*((volatile unsigned short*)(type01_01_05_base + type01_01_05n_offset)) = (unsigned short)(unsigned short)0x0100);\n\n\n\n\n" " *((volatile unsigned char*)0x02010004) = (unsigned char)0x04;\n" " *((volatile unsigned char*)0x02010008) = (unsigned char)0x05;\n\n" " *((volatile unsigned short*)0x02020004) = (unsigned short)0x0400;\n" " *((volatile unsigned short*)0x02020008) = (unsigned short)0x0500;\n\n" " *((volatile unsigned long*)0x02030004) = (unsigned long)(0x00030000 + 0x00010000);\n" " *((volatile unsigned long*)0x02030008) = (unsigned long)(0x00030000 + 0x00020000);\n\n" " (*((volatile unsigned char*)0x02040004) = (unsigned char)(unsigned char)(0x0A - 0x02));\n" " (*((volatile unsigned char*)0x02040008) = (unsigned char)(unsigned char)(0x0A - 0x01));\n\n" " (*((volatile unsigned short*)0x02050004) = (unsigned short)(unsigned short)(0x0001 << 11));\n" " (*((volatile unsigned short*)0x02050008) = (unsigned short)(unsigned short)(0x0001 << 12));\n\n" " (*((volatile unsigned long*)0x02060004) = (unsigned long)(unsigned long)(0x80000000 | 0x00080000));\n" " (*((volatile unsigned long*)0x02060008) = (unsigned long)(unsigned long)(0x80000000 | 0x00800000));\n\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html