NAME

Mail::Message::Head::Subset - subset of header information of a message

INHERITANCE

 Mail::Message::Head::Subset realizes a Mail::Message::Head::Complete

 Mail::Message::Head::Subset
   is a Mail::Message::Head
   is a Mail::Reporter

SYNOPSIS

 my $subset = Mail::Message::Head::Subset->new(...)
 $subset->isa('Mail::Message::Head')  # true
 $subset->guessBodySize               # integer or undef
 $subset->isDelayed                   # true

DESCRIPTION

Some types of folders contain an index file which lists a few lines of information per messages. Especially when it is costly to read header lines, the index speeds-up access considerably. For instance, the subjects of all messages are often wanted, but waiting for a thousand messages of the folder to be read may imply a thousand network reads (IMAP) or file openings (MH)

When you access header fields which are not in the header subset, the whole header has to be parsed (which may consume considerable time, depending on the type of folder).

OVERLOADED

overload: "": See "OVERLOADED" in Mail::Message::Head
overload: bool: See "OVERLOADED" in Mail::Message::Head

METHODS

Constructors

Mail::Message::Head::Subset->build([PAIR|FIELD]-LIST): See "Constructors" in Mail::Message::Head
Mail::Message::Head::Subset->new(OPTIONS): See "Constructors" in Mail::Message::Head

The header

$obj->isDelayed: See "The header" in Mail::Message::Head
$obj->isEmpty: See "The header" in Mail::Message::Head
$obj->isModified: See "The header" in Mail::Message::Head
$obj->knownNames: See "The header" in Mail::Message::Head
$obj->message([MESSAGE]): See "The header" in Mail::Message::Head
$obj->modified([BOOLEAN]): See "The header" in Mail::Message::Head
$obj->orderedFields: See "The header" in Mail::Message::Head

Access to the header

$obj->count(NAME): Count the number of fields with this NAME. If the NAME cannot be found, the full header get loaded. In case we find any NAME field, it is decided we know all of them, and loading is not needed.
$obj->get(NAME [,INDEX]): Get the data which is related to the field with the NAME. The case of the characters in NAME does not matter. When a NAME is used which is not known yet, realization will take place.
$obj->study(NAME [,INDEX]): See "Access to the header" in Mail::Message::Head

About the body

$obj->guessBodySize: The body size is defined in the Content-Length field. However, this field may not be known. In that case, a guess is made based on the known Lines field. When also that field is not known yet, undef is returned.
$obj->isMultipart: See "About the body" in Mail::Message::Head

Internals

$obj->addNoRealize(FIELD): See "Internals" in Mail::Message::Head
$obj->addOrderedFields(FIELDS): See "Internals" in Mail::Message::Head
$obj->fileLocation: See "Internals" in Mail::Message::Head
$obj->load: See "Internals" in Mail::Message::Head
$obj->moveLocation(DISTANCE): See "Internals" in Mail::Message::Head
$obj->read(PARSER): See "Internals" in Mail::Message::Head
$obj->setNoRealize(FIELD): See "Internals" in Mail::Message::Head

Error handling

$obj->AUTOLOAD: See "Error handling" in Mail::Reporter
$obj->addReport(OBJECT): See "Error handling" in Mail::Reporter
$obj->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])
Mail::Message::Head::Subset->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK]): See "Error handling" in Mail::Reporter
$obj->errors: See "Error handling" in Mail::Reporter
$obj->log([LEVEL [,STRINGS]])
Mail::Message::Head::Subset->log([LEVEL [,STRINGS]]): See "Error handling" in Mail::Reporter
$obj->logPriority(LEVEL)
Mail::Message::Head::Subset->logPriority(LEVEL): See "Error handling" in Mail::Reporter
$obj->logSettings: See "Error handling" in Mail::Reporter
$obj->notImplemented: See "Error handling" in Mail::Reporter
$obj->report([LEVEL]): See "Error handling" in Mail::Reporter
$obj->reportAll([LEVEL]): See "Error handling" in Mail::Reporter
$obj->trace([LEVEL]): See "Error handling" in Mail::Reporter
$obj->warnings: See "Error handling" in Mail::Reporter

Cleanup

$obj->DESTROY: See "Cleanup" in Mail::Reporter
$obj->inGlobalDestruction: See "Cleanup" in Mail::Reporter

DIAGNOSTICS

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.

LICENSE

Copyrights 2001-2011 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://www.perl.com/perl/misc/Artistic.html