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Changes in version 2.21
-----------------------

* New documentation.

* User defined subroutines should use 'die' to signal errors.

* User defined subroutines can preliminary terminate options
  processing by calling die("FINISH");

* Correct erroneous install of Getopt::Long manpage.
  Previous versions seem to install Getopt::GetoptLong instead of
  Getopt::Long.

Changes in version 2.20
-----------------------

* Prevent the magic argument "<>" from being interpreted as option
  starter characters if it is the first argument passed.
  To use the characters "<>" as option starters, pass "><" instead.

* Changed license: Getopt::Long may now also be used under the Perl
  Artistic License.

* Changed the file name of the distribution kit from "GetoptLong..."
  to "Getopt-Long-..." to match the standards.

Changes in version 2.19
-----------------------

* Fix a warning bug with bundling_override.

There's no version 2.18
-----------------------

Changes in version 2.17
-----------------------

* Getopt::Long::config is renamed Getopt::Long::Configure. The old
  name will remain supported without being documented.

* Options can have the specifier '+' to denote that the option value
  must be incremented each time the option occurs on the command line.
  For example:

     my $more = 2;
     Getopt::Long::Configure("bundling");
     GetOptions ("v+" => \$more);
     print STDOUT ("more = $more\n");

  will print "more = 3" when called with "-v", "more = 4" when called
  with "-vv" (or "-v -v"), and so on.

* Getopt::Long now uses autoloading. This substantially reduces the
  resources required to 'use Getopt::Long' (about 100 lines of over
  1300 total).

* It is now documented that global option variables like $opt_foo
  need to be declared using 'use vars ...' when running under 'use
  strict'. 

* To install, it is now required to use the official procedure:

     perl Makefile.PL
     make
     make test
     make install

Changes in version 2.16
-----------------------

* A couple of small additional fixes to the $` $& $' fixes.

* The option prefix can be set using config("prefix=...") or, more
  powerful, with config("prefix_pattern=..."); see the documentation
  for details.

* More 'perl -w' warnings eliminated for obscure cases of bundling.

This version is identical to 2.15, which was not released.

There's no version 2.14
-----------------------

Changes in version 2.13
-----------------------

* All regexps are changed to avoid the use of $`, $& and $'. Using one
  of these causes all pattern matches in the program to be much slower
  than necessary.

* Configuration errors are signalled using die() and will cause the
  program to be terminated (unless eval{...} or $SIG{__DIE__} is
  used).

* Option parsing errors are now signalled with calls to warn().

* In option bundles, numeric values may be embedded in the bundle
  (e.g. -al24w80).

* More 'perl -w' warnings eliminated for obscure cases of bundling.

* Removed non-standard version number matching. Version 1.121 is now
  more than 1.12 but less than 1.13. 

Changes in version 2.12
-----------------------

* A single question mark is allowed as an alias to an option, e.g. 

    GetOptions ("help|?", ...)

Changes in version 2.11
-----------------------

* User linkage may be an object, provided the object is really a hash.

  For example:

    {	package Foo;
	sub new () { return bless {}; }
    }

    my $linkage = Foo->new();

    GetOptions ($linkage, ... );

* Some bug fixes in handling obscure cases of pass-through.

Changes in version 2.9
----------------------

* A new way to configure Getopt::Long. Instead of setting module local
  variables, routine Getopt::Long::config can be called with the names
  of options to be set or reset, e.g.

    Getopt::Long::config ("no_auto_abbrev", "ignore_case");

  Configuring by using the module local variables is deprecated, but
  it will continue to work for backwark compatibility.

Changes in version 2.6
----------------------

* Handle ignorecase even if autoabbrev is off. 

* POD corrections.

Changes in version 2.4
----------------------

* Pass-through of unrecognized options. Makes it easy to write wrapper
  programs that process some of the command line options but pass the
  others to another program.

* Options can be of type HASH, now you can say

    --define foo=bar

  and have $opt_define{"foo"} set to "bar".

* An enhanced skeleton program, skel2.pl, that combines the power of
  Getopt::Long with Pod::Usage. 
  Module Pod::Usage can be obtained from CPAN,
  http://www.perl.com/CPAN/authors/Brad_Appleton. 

Possible incompatibility in version 2.4
---------------------------------------

Previous versions of Getopt::Long always downcased the option variable
names when ignorecase was in effect. This bug has been corrected. As a
consequence, &GetOptions ("Foo") will now set variable $opt_Foo
instead of $opt_foo.