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CPAN::Changes::Spec(3pm) User Contributed Perl Documentation CPAN::Changes::Spec(3pm)


CPAN::Changes::Spec - Specification for CPAN Changes files


version 0.04


    Revision history for perl module Foo::Bar
    0.02 2009-07-17
     - Added more foo() tests
    0.01 2009-07-16
     - Initial release


This document describes version 0.03 of the specification for Changes files included in a CPAN distribution.

It is intended as a guide for module authors to encourage them to write meaningful changelogs as well as provide a programmatic interface to reliably read and write Changes files.



Versions should be formatted as described in "Version-Formats" in CPAN::Meta::Spec.


A date/time in the format specified by <> aka W3CDTF. Note: The "T" marker before the time portion is optional.

In order to satisfy release events not made to the public, or dates that are historically unknown, the following strings are also available:

  • Unknown Release Date
  • Unknown
  • Not Released
  • Development Release
  • Development
  • Developer Release


Required Elements

In its simplest form, the only required elements are a "Version", a "Date" and the noted changes. Blank lines between the "Version" line and the first "Change" line are optional. Blank lines between "Change" lines are also optional.

    <Version>(whitespace/non-"word" characters)<Date>

NOTE: The characters between a "Version" and a "Date" must start with whitespace, but may subsquently contain any combination of whitespace and non-"word" characters. Example:

    0.01 - 2013-12-11

"Change" lines have no specific format. Commonly, authors will use a dash "-" followed by a space to start a new change, and indent subsequent lines for multi-line changes. Example

    - Simple Change
    - This is a very very very long
      change line

Although there is no limit on line length, authors generally wrap each line at 78 columns.

Optional Elements

Release Note

Any text following the "Date" portion of the "Version" line will be considered the "Release Note". Example:

    0.01 2013-04-01 Codename: April Fool
      - First Release


Any amount of text before the first "Version" line will be considered part of the preamble. Most existing distributions include something along the lines of:

    Revision history for perl module My::Module


    Revision history for perl distribution My-Distribution


Changelog entries may be grouped under headings. Heading lines begin with an opening square bracket ("["), and end with a matching square bracket ("]"). When parsing group headings, leading and trailing whitespace inside the brackets should be discarded.

    (whitespace)[Grouping Name]

Since empty lines hold no special meaning, all "Change" lines will fall under the current group until a new group heading is found. Example:

    [ First Group ]
    - First Change
    - Second Change; in first group
    [ Second Group ]
    - First Change; in second group


Basic Example

    0.01 2009-07-16
     - Initial release

Example with a preamble

    Revision history for perl module Foo::Bar
    0.02 2009-07-17
     - Added more foo() tests
    0.01 2009-07-16
     - Initial release

Example with groups

    Revision history for perl module Foo::Bar
    0.03 2009-07-18
     [Important Security Information]
     - This release fixes critical bug RT #1234
     [Other Changes]
     - Added some feature
    0.02 2009-07-17
     - Added more foo() tests
    0.01 2009-07-16T19:20:30+01:00
     - Initial release


  • CPAN::Changes
  • Test::CPAN::Changes


Brian Cassidy <>


Copyright 2011-2013 by Brian Cassidy

This is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

2022-06-12 perl v5.34.0