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

/
/
gms

Test String

Code Generator

Language

Generated Code

use strict; my $str = '{ "first_page_uri": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?PageSize=1000&Page=0", "end": 387, "previous_page_uri": null, "uri": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?PageSize=1000&Page=0", "page_size": 1000, "start": 0, "usage_records": [ { "category": "wireless-usage", "description": "SIM Usage", "account_sid": "ACd7a7c24a3c7b0b0ddcde452fd6c18aae", "start_date": "2023-01-01", "end_date": "2023-01-31", "as_of": "2023-02-05T06:53:40+00:00", "count": "0", "count_unit": "units", "usage": "0", "usage_unit": "units", "price": "0", "price_unit": "usd", "api_version": "2010-04-01", "uri": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=wireless-usage&StartDate=2023-01-01&EndDate=2023-01-31", "subresource_uris": { "all_time": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/AllTime.json?Category=wireless-usage", "today": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Today.json?Category=wireless-usage", "yesterday": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yesterday.json?Category=wireless-usage", "this_month": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/ThisMonth.json?Category=wireless-usage", "last_month": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=wireless-usage", "daily": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Daily.json?Category=wireless-usage", "monthly": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Monthly.json?Category=wireless-usage", "yearly": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yearly.json?Category=wireless-usage" } }, { "category": "pv-basic-rooms", "description": "Go Rooms", "account_sid": "ACd7a7c24a3c7b0b0ddcde452fd6c18aae", "start_date": "2023-01-01", "end_date": "2023-01-31", "as_of": "2023-02-05T06:53:40+00:00", "count": "0", "count_unit": "", "usage": "0", "usage_unit": "", "price": "0", "price_unit": "usd", "api_version": "2010-04-01", "uri": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=pv-basic-rooms&StartDate=2023-01-01&EndDate=2023-01-31", "subresource_uris": { "all_time": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/AllTime.json?Category=pv-basic-rooms", "today": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Today.json?Category=pv-basic-rooms", "yesterday": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yesterday.json?Category=pv-basic-rooms", "this_month": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/ThisMonth.json?Category=pv-basic-rooms", "last_month": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/LastMonth.json?Category=pv-basic-rooms", "daily": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Daily.json?Category=pv-basic-rooms", "monthly": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Monthly.json?Category=pv-basic-rooms", "yearly": "/2010-04-01/Accounts/ACd7a7c24a3c7b0b0ddcde452fd6c18aae/Usage/Records/Yearly.json?Category=pv-basic-rooms" } }, '; my $regex = qr/,\s*("subresource_uris":.[^}]*[}])/msp; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html