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"dcs.lustre.device.ost.attributes\[.*-((.*).+?),.*,rate\]") test_str = ("[\n" "{\n" "itemid: \"26940\",\n" "status: \"0\",\n" "lastvalue: \"60843699081216\",\n" "lastclock: \"1454321651\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0000,kbytesavail]\",\n" "name: \"OST0000 available space\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"60\",\n" "value_type: \"3\",\n" "units: \"Bytes\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26943\",\n" "status: \"0\",\n" "lastvalue: \"61486384615424\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0001,kbytesfree]\",\n" "name: \"OST0001 free space\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26944\",\n" "status: \"0\",\n" "lastvalue: \"62068190941184\",\n" "lastclock: \"1454272094\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0000,kbytestotal]\",\n" "name: \"OST0000 total space\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"86400\",\n" "value_type: \"3\",\n" "units: \"Bytes\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26945\",\n" "status: \"0\",\n" "lastvalue: \"62068190941184\",\n" "lastclock: \"1454272092\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0001,kbytestotal]\",\n" "name: \"OST0001 total space\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"86400\",\n" "value_type: \"3\",\n" "units: \"Bytes\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26946\",\n" "status: \"0\",\n" "lastvalue: \"0\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0000,read_bytes,rate]\",\n" "name: \"OST0000 read\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes/sec\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26942\",\n" "status: \"0\",\n" "lastvalue: \"61477895307264\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0000,kbytesfree]\",\n" "name: \"OST0000 free space\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26951\",\n" "status: \"0\",\n" "lastvalue: \"2878341087\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0001,write_bytes,rate]\",\n" "name: \"OST0001 write\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes/sec\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26950\",\n" "status: \"0\",\n" "lastvalue: \"3185573852\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0000,write_bytes,rate]\",\n" "name: \"OST0000 write\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes/sec\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "},\n" "{\n" "itemid: \"26947\",\n" "status: \"0\",\n" "lastvalue: \"0\",\n" "lastclock: \"1454321686\",\n" "key_: \"dcs.lustre.device.ost.attributes[plexfs-OST0001,read_bytes,rate]\",\n" "name: \"OST0001 read\",\n" "hostname: \"lustre_plexfs\",\n" "value: \"lustre\",\n" "delay: \"5\",\n" "value_type: \"3\",\n" "units: \"Bytes/sec\",\n" "category: \"performance\",\n" "type: \"filesystem\",\n" "history: \"90\"\n" "}\n" "]") match = regex.search(test_str) if match: print(f"Match 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