phpman > perldoc > Mail::Message::Head::FieldGroup(3pm)

NAME
    Mail::Message::Head::FieldGroup - a sub set of fields in a header

INHERITANCE
     Mail::Message::Head::FieldGroup
       is a Mail::Reporter

     Mail::Message::Head::FieldGroup is extended by
       Mail::Message::Head::ListGroup
       Mail::Message::Head::ResentGroup
       Mail::Message::Head::SpamGroup

SYNOPSIS
    Never instantiated directly.

DESCRIPTION
    Some fields have a combined meaning: a set of fields which represent one intermediate step
    during the transport of the message (a *resent group*, implemented in
    Mail::Message::Head::ResentGroup), fields added by mailing list software (implemented in
    Mail::Message::Head::ListGroup), or fields added by Spam detection related software (implemented
    by Mail::Message::Head::SpamGroup). Each set of fields can be extracted or added as group with
    objects which are based on the implementation in this class.

    Extends "DESCRIPTION" in Mail::Reporter.

METHODS
    Extends "METHODS" in Mail::Reporter.

  Constructors
    Extends "Constructors" in Mail::Reporter.

    $obj->clone()
        Make a copy of this object. The collected fieldnames are copied and the list type
        information. No deep copy is made for the header: this is only copied as reference.

    $obj->from($head|$message)
        Create a group of fields based on the specified $message or message $head. This may return
        one or more of the objects, which depends on the type of group. Mailing list fields are all
        stored in one object, where resent and spam groups can appear more than once.

    $obj->implementedTypes()
    Mail::Message::Head::FieldGroup->implementedTypes()
        Returns a list of strings containing all possible return values for type().

    Mail::Message::Head::FieldGroup->new($fields, %options)
        Construct an object which maintains one set of header $fields. The $fields may be specified
        as "Mail::Message::Field" objects or as key-value pairs. The %options and $fields (as
        key-value pair) can be mixed: they are distinguished by their name, where the fields always
        start with a capital. The field objects must aways lead the %options.

         -Option  --Defined in     --Default
          head                       undef
          log       Mail::Reporter   'WARNINGS'
          software                   undef
          trace     Mail::Reporter   'WARNINGS'
          type                       undef
          version                    undef

        head => HEAD
          The header HEAD object is used to store the grouped fields in. If no header is specified,
          a Mail::Message::Head::Partial is created for you. If you wish to scan the existing fields
          in a header, then use the from() method.

        log => LEVEL
        software => STRING
          Name of the software which produced the fields.

        trace => LEVEL
        type => STRING
          Group name for the fields. Often the same, or close to the same STRING, as the "software"
          option contains.

        version => STRING
          Version number for the software which produced the fields.

  The header
    $obj->add( <$field, $value> | $object )
        Add a field to the header, using the field group. When the field group is already attached
        to a real message header, it will appear in that one as well as being registered in this
        set. If no header is defined, the field only appears internally.

        example: adding a field to a detached list group

         my $this = Mail::Message::Head::ListGroup->new(...);
         $this->add('List-Id' => 'mailbox');
         $msg->addListGroup($this);
         $msg->send;

        example: adding a field to an attached list group

         my $lg = Mail::Message::Head::ListGroup->from($msg);
         $lg->add('List-Id' => 'mailbox');

    $obj->addFields( [$fieldnames] )
        Add some $fieldnames to the set.

    $obj->attach($head)
        Add a group of fields to a message $head. The fields will be cloned(!) into the header, so
        that the field group object can be used again.

        example: attaching a list group to a message

         my $lg = Mail::Message::Head::ListGroup->new(...);
         $lg->attach($msg->head);
         $msg->head->addListGroup($lg);   # same

         $msg->head->addSpamGroup($sg);   # also implemented with attach

    $obj->delete()
        Remove all the header lines which are combined in this fields group, from the header.

    $obj->fieldNames()
        Return the names of the fields which are used in this group.

    $obj->fields()
        Return the fields which are defined for this group.

    $obj->head()
        Returns the header object, which includes these fields.

  Access to the header
    $obj->software()
        Returns the name of the software as is defined in the headers. The may be slightly different
        from the return value of type(), but usually not too different.

    $obj->type()
        Returns an abstract name for the field group; which software is controlling it. "undef" is
        returned in case the type is not known. Valid names are group type dependent: see the
        applicable manual pages. A list of all types can be retrieved with implementedTypes().

    $obj->version()
        Returns the version number of the software used to produce the fields. Some kinds of
        software do leave such a trace, other cases will return "undef"

  Internals
    $obj->collectFields( [$name] )
        Scan the header for fields which are usually contained in field group with the specified
        $name. For mailinglist groups, you can not specify a $name: only one set of headers will be
        found (all headers are considered to be produced by exactly one package of mailinglist
        software).

        This method is automatically called when a field group is constructed via from() on an
        existing header or message.

        Returned are the names of the list header fields found, in scalar context the amount of
        fields. An empty list/zero indicates that there was no group to be found.

        Please warn the author of MailBox if you see that to few or too many fields are included.

    $obj->detected($type, $software, $version)
        Sets the values for the field group type, software, and version, prossibly to "undef".

  Error handling
    Extends "Error handling" in Mail::Reporter.

    $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, $callback] )
    Mail::Message::Head::FieldGroup->defaultTrace( [$level]|[$loglevel, $tracelevel]|[$level,
    $callback] )
        Inherited, see "Error handling" in Mail::Reporter

    $obj->details()
        Produce information about the detected/created field group, which may be helpful during
        debugging. A nicely formatted string is returned.

    $obj->errors()
        Inherited, see "Error handling" in Mail::Reporter

    $obj->log( [$level, [$strings]] )
    Mail::Message::Head::FieldGroup->log( [$level, [$strings]] )
        Inherited, see "Error handling" in Mail::Reporter

    $obj->logPriority($level)
    Mail::Message::Head::FieldGroup->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

    $obj->print( [$fh] )
        Print the group to the specified $fh or GLOB. This is probably only useful for debugging
        purposed. The output defaults to the selected file handle.

    $obj->report( [$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::Reporter.

    $obj->DESTROY()
        Inherited, 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.

SEE ALSO
    This module is part of Mail-Message distribution version 3.012, built on February 11, 2022.
    Website: http://perl.overmeer.net/CPAN/

LICENSE
    Copyrights 2001-2022 by [Mark Overmeer <markov AT cpan.org>]. 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/