Provided by: libmail-message-perl_3.006-1_all 
NAME
Mail::Message::Head::Partial - subset of header information of a message
INHERITANCE
Mail::Message::Head::Partial
is a Mail::Message::Head::Complete
is a Mail::Message::Head
is a Mail::Reporter
SYNOPSIS
my $partial = $head->strip;
$partial->isa('Mail::Message::Head') # true
$partial->isDelayed # false
$partial->isPartial # true
$partial->removeFields( qr/^X-/ );
$partial->removeFieldsExcept( qw/To From/ );
$partial->removeResentGroups;
$partial->removeListGroup;
$partial->removeSpamGroups;
DESCRIPTION
Header information consumes a considerable amount of memory. Most of this information is
only useful during a short period of time in your program, or sometimes it is not used at
all. You then can decide to remove most of the header information. However, be warned
that it will be lost permanently: the header (and therefore the message) gets mutulated!
Extends "DESCRIPTION" in Mail::Message::Head::Complete.
OVERLOADED
Extends "OVERLOADED" in Mail::Message::Head::Complete.
overload: ""
Inherited, see "OVERLOADED" in Mail::Message::Head
overload: bool
Inherited, see "OVERLOADED" in Mail::Message::Head
METHODS
Extends "METHODS" in Mail::Message::Head::Complete.
Constructors
Extends "Constructors" in Mail::Message::Head::Complete.
Mail::Message::Head::Partial->build( [PAIR|$field], ... )
Inherited, see "Constructors" in Mail::Message::Head::Complete
$obj->clone( [@names|ARRAY|Regexps] )
Inherited, see "Constructors" in Mail::Message::Head::Complete
Mail::Message::Head::Partial->new(%options)
Inherited, see "Constructors" in Mail::Message::Head
The header
Extends "The header" in Mail::Message::Head::Complete.
$obj->isDelayed()
Inherited, see "The header" in Mail::Message::Head
$obj->isEmpty()
Inherited, see "The header" in Mail::Message::Head
$obj->isModified()
Inherited, see "The header" in Mail::Message::Head
$obj->knownNames()
Inherited, see "The header" in Mail::Message::Head
$obj->message( [$message] )
Inherited, see "The header" in Mail::Message::Head
$obj->modified( [BOOLEAN] )
Inherited, see "The header" in Mail::Message::Head
$obj->nrLines()
Inherited, see "The header" in Mail::Message::Head::Complete
$obj->orderedFields()
Inherited, see "The header" in Mail::Message::Head
$obj->size()
Inherited, see "The header" in Mail::Message::Head::Complete
$obj->wrap($integer)
Inherited, see "The header" in Mail::Message::Head::Complete
Access to the header
Extends "Access to the header" in Mail::Message::Head::Complete.
$obj->add( $field | $line | <$name, $body, [$attrs]> )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->addListGroup($object)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->addResentGroup($resent_group|$data)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->addSpamGroup($object)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->cleanupOrderedFields()
The header maintains a list of fields which are ordered in sequence of definition. It
is required to maintain the header order to keep the related fields of resent groups
together. The fields are also included in a hash, sorted on their name for fast
access.
The references to field objects in the hash are real, those in the ordered list are
weak. So when field objects are removed from the hash, their references in the
ordered list are automagically undef'd.
When many fields are removed, for instance with removeFields() or
removeFieldsExcept(), then it is useful to remove the list of undefs from the ordered
list as well. In those cases, this method is called automatically, however you may
have your own reasons to call this method.
$obj->count($name)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->delete($name)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->get( $name, [$index] )
Inherited, see "Access to the header" in Mail::Message::Head
$obj->grepNames( [@names|ARRAY|Regexps] )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->listGroup()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->names()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->print( [$fh] )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->printSelected($fh, <STRING|Regexp>, ...)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->printUndisclosed( [$fh] )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->removeContentInfo()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->removeField($field)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->removeFields( <STRING|Regexp>, ... )
Remove the fields from the header which are exactly named 'STRING' (case insensitive)
or match the regular expresssion. Do not forget to add the 'i' modifier to the
regexp, because fields are case insensitive.
See also removeField() which is used to remove one field object from the header. The
reverse specification can be made with "removeFieldsExcept()".
example:
$head->removeFields('bcc', 'received');
$head->removeFields( qr/^content-/i );
$obj->removeFieldsExcept(STRING|Regexp, ...)
Remove all fields from the header which are not equivalent to one of the specified
STRINGs (case-insensitive) and which are not matching one of the REGular EXPressions.
Do not forget to add the 'i' modifier to the Regexp, because fields are case
insensitive.
See also removeField() which is used to remove one field object from the header. The
reverse specification can be made with "removeFields()".
example:
$head->removeFieldsExcept('subject', qr/^content-/i );
$head->removeFieldsExcept( qw/subject to from sender cc/ );
$obj->removeListGroup()
Removes all header lines which are used to administer mailing lists. Which fields
that are is explained in Mail::Message::Head::ListGroup. Returned is the number of
removed lines.
$obj->removeResentGroups()
Removes all header lines which are member of a resent group, which are explained in
Mail::Message::Head::ResentGroup. Returned is the number of removed lines.
For removing single groups (for instance because you want to keep the last), use
Mail::Message::Head::FieldGroup::delete().
$obj->removeSpamGroups()
Removes all header lines which were produced by spam detection and spam-fighting
software. Which fields that are is explained in Mail::Message::Head::SpamGroup.
Returned is the number of removed lines.
$obj->resentGroups()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->reset($name, @fields)
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->set( $field | $line | <$name, $body, [$attrs]> )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->spamDetected()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->spamGroups( [$names] )
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->string()
Inherited, see "Access to the header" in Mail::Message::Head::Complete
$obj->study( $name, [$index] )
Inherited, see "Access to the header" in Mail::Message::Head
About the body
Extends "About the body" in Mail::Message::Head::Complete.
$obj->guessBodySize()
Inherited, see "About the body" in Mail::Message::Head
$obj->guessTimeStamp()
Inherited, see "About the body" in Mail::Message::Head::Complete
$obj->isMultipart()
Inherited, see "About the body" in Mail::Message::Head
$obj->recvstamp()
Inherited, see "About the body" in Mail::Message::Head::Complete
$obj->timestamp()
Inherited, see "About the body" in Mail::Message::Head::Complete
Internals
Extends "Internals" in Mail::Message::Head::Complete.
$obj->addNoRealize($field)
Inherited, see "Internals" in Mail::Message::Head
$obj->addOrderedFields($fields)
Inherited, see "Internals" in Mail::Message::Head
$obj->createFromLine()
Inherited, see "Internals" in Mail::Message::Head::Complete
$obj->createMessageId()
Inherited, see "Internals" in Mail::Message::Head::Complete
$obj->fileLocation()
Inherited, see "Internals" in Mail::Message::Head
$obj->load()
Inherited, see "Internals" in Mail::Message::Head
$obj->messageIdPrefix( [$prefix, [$hostname]|CODE] )
Mail::Message::Head::Partial->messageIdPrefix( [$prefix, [$hostname]|CODE] )
Inherited, see "Internals" in Mail::Message::Head::Complete
$obj->moveLocation($distance)
Inherited, see "Internals" in Mail::Message::Head
$obj->read($parser)
Inherited, see "Internals" in Mail::Message::Head
$obj->setNoRealize($field)
Inherited, see "Internals" in Mail::Message::Head
Error handling
Extends "Error handling" in Mail::Message::Head::Complete.
$obj->AUTOLOAD()
Inherited, see "Error handling" in Mail::Reporter
$obj->addReport($object)
Inherited, see "Error handling" in Mail::Reporter
$obj->defaultTrace( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )
Mail::Message::Head::Partial->defaultTrace( [$level]|[$loglevel, $tracelevel]|[$level,
$callback] )
Inherited, see "Error handling" in Mail::Reporter
$obj->errors()
Inherited, see "Error handling" in Mail::Reporter
$obj->log( [$level, [$strings]] )
Mail::Message::Head::Partial->log( [$level, [$strings]] )
Inherited, see "Error handling" in Mail::Reporter
$obj->logPriority($level)
Mail::Message::Head::Partial->logPriority($level)
Inherited, see "Error handling" in Mail::Reporter
$obj->logSettings()
Inherited, see "Error handling" in Mail::Reporter
$obj->notImplemented()
Inherited, see "Error handling" in Mail::Reporter
$obj->report( [$level] )
Inherited, see "Error handling" in Mail::Reporter
$obj->reportAll( [$level] )
Inherited, see "Error handling" in Mail::Reporter
$obj->trace( [$level] )
Inherited, see "Error handling" in Mail::Reporter
$obj->warnings()
Inherited, see "Error handling" in Mail::Reporter
Cleanup
Extends "Cleanup" in Mail::Message::Head::Complete.
$obj->DESTROY()
Inherited, see "Cleanup" in Mail::Reporter
DETAILS
Extends "DETAILS" in Mail::Message::Head::Complete.
Ordered header fields
Extends "Ordered header fields" in Mail::Message::Head::Complete.
Head class implementation
Extends "Head class implementation" in Mail::Message::Head::Complete.
Subsets of header fields
Extends "Subsets of header fields" in Mail::Message::Head::Complete.
Reducing the header size
A message header is very large in memory and quite large on disk, and therefore a good
candidate for size reduction. One way to reduce the size is by simply eliminating
superfluous header fields. Each field requires at least 100 bytes of run-time memory, so
this may help!
Before you start playing around with removeFields() and removeFieldsExcept(), you may take
a look at two large groups of fields which can be removes as sets: the resent headers and
the mailinglist headers.
Resent headers describe the intermediate steps in the transmission process for the
messages. After successful delivery, they are rarely useful.
When you are archiving a mailinglist, it is hardly ever useful to store a the list
administration lines for each message as well.
. see examples/reduce.pl in distribution
foreach my $msg ($folder->messages)
{ $msg->head->removeResentGroups;
$msg->head->removeResentList;
}
DIAGNOSTICS
Warning: Cannot remove field $name from header: not found.
You ask to remove a field which is not known in the header. Using delete(), reset(),
or set() to do the job will not result in warnings: those methods check the existence
of the field first.
Warning: Field objects have an implied name ($name)
Error: Package $package does not implement $method.
Fatal error: the specific package (or one of its superclasses) does not implement this
method where it should. This message means that some other related classes do
implement this method however the class at hand does not. Probably you should
investigate this and probably inform the author of the package.
SEE ALSO
This module is part of Mail-Message distribution version 3.006, built on January 24, 2018.
Website: http://perl.overmeer.net/CPAN/
LICENSE
Copyrights 2001-2018 by [Mark Overmeer]. For other contributors see ChangeLog.
This program is free software; you can redistribute it and/or modify it under the same
terms as Perl itself. See http://dev.perl.org/licenses/