=encoding utf8

=head1 NAME

Mail::Message::Body::Nested - body of a message which contains a message

=head1 INHERITANCE

 Mail::Message::Body::Nested
   is a Mail::Message::Body
   is a Mail::Reporter

=head1 SYNOPSIS

 See Mail::Message::Body

 if($body->isNested) {
    my $nest = $body->nested;
    $nest->delete;
 }

=head1 DESCRIPTION

The body (content) of a message can be stored in various ways.  In this
manual-page you find the description of extra functionality you have
when a message contains a nested message, like C<message/rfc822>.

A nested message is different from a multipart message which contains
only one element, because a nested message has a full set of message
header fields defined by the RFC882, where a part of a multipart has
only a few.  But because we do not keep track whether all fields are
presented, a C<Mail::Message::Part> is used anyway.

Extends L<"DESCRIPTION" in Mail::Message::Body|Mail::Message::Body/"DESCRIPTION">.
 
=head1 OVERLOADED

Extends L<"OVERLOADED" in Mail::Message::Body|Mail::Message::Body/"OVERLOADED">.
 
=over 4

=item overload: B<"">

Inherited, see L<Mail::Message::Body/"OVERLOADED">

=item overload: B<'==' and '!='>

Inherited, see L<Mail::Message::Body/"OVERLOADED">

=item overload: B<@{}>

Inherited, see L<Mail::Message::Body/"OVERLOADED">

=item overload: B<bool>

Inherited, see L<Mail::Message::Body/"OVERLOADED">

=back

=head1 METHODS

Extends L<"METHODS" in Mail::Message::Body|Mail::Message::Body/"METHODS">.
 
=head2 Constructors

Extends L<"Constructors" in Mail::Message::Body|Mail::Message::Body/"Constructors">.
 
=over 4

=item $obj-E<gt>B<clone>()

Inherited, see L<Mail::Message::Body/"Constructors">

=item Mail::Message::Body::Nested-E<gt>B<new>(%options)

 -Option           --Defined in         --Default
  based_on           Mail::Message::Body  undef
  charset            Mail::Message::Body  'PERL' or <undef>
  checked            Mail::Message::Body  <false>
  content_id         Mail::Message::Body  undef
  data               Mail::Message::Body  undef
  description        Mail::Message::Body  undef
  disposition        Mail::Message::Body  undef
  eol                Mail::Message::Body  'NATIVE'
  file               Mail::Message::Body  undef
  filename           Mail::Message::Body  undef
  log                Mail::Reporter       'WARNINGS'
  message            Mail::Message::Body  undef
  mime_type          Mail::Message::Body  'message/rfc822'
  modified           Mail::Message::Body  <false>
  nested                                  undef
  trace              Mail::Reporter       'WARNINGS'
  transfer_encoding  Mail::Message::Body  'none'

=over 2

=item based_on => BODY

=item charset => CHARSET|'PERL'

=item checked => BOOLEAN

=item content_id => STRING

=item data => ARRAY-OF-LINES | STRING

=item description => STRING|FIELD

=item disposition => STRING|FIELD

=item eol => 'CR'|'LF'|'CRLF'|'NATIVE'

=item file => FILENAME|FILEHANDLE|IOHANDLE

=item filename => FILENAME

=item log => LEVEL

=item message => MESSAGE

=item mime_type => STRING|FIELD|MIME

=item modified => BOOLEAN

=item nested => MESSAGE

The message which is encapsulated within this body.

=item trace => LEVEL

=item transfer_encoding => STRING|FIELD

=back

example: 

 my $msg   = $folder->message(3);
 my $encaps= Mail::Message::Body::Nested->new(nested => $msg);

 # The body will be coerced into a message, which lacks a few
 # lines but we do not bother.
 my $intro = Mail::Message::Body->new(data => ...);
 my $body  = Mail::Message::Body::Nested->new(nested  => $intro);

=back

=head2 Constructing a body

Extends L<"Constructing a body" in Mail::Message::Body|Mail::Message::Body/"Constructing a body">.
 
=over 4

=item $obj-E<gt>B<attach>($messages, %options)

Inherited, see L<Mail::Message::Body::Construct/"Constructing a body">

=item $obj-E<gt>B<check>()

Inherited, see L<Mail::Message::Body::Encode/"Constructing a body">

=item $obj-E<gt>B<concatenate>($components)

Inherited, see L<Mail::Message::Body::Construct/"Constructing a body">

=item $obj-E<gt>B<decoded>(%options)

Inherited, see L<Mail::Message::Body/"Constructing a body">

=item $obj-E<gt>B<encode>(%options)

Inherited, see L<Mail::Message::Body::Encode/"Constructing a body">

=item $obj-E<gt>B<encoded>()

Inherited, see L<Mail::Message::Body::Encode/"Constructing a body">

=item $obj-E<gt>B<eol>( ['CR'|'LF'|'CRLF'|'NATIVE'] )

Inherited, see L<Mail::Message::Body/"Constructing a body">

=item $obj-E<gt>B<foreachLine>((CODE))

It is NOT possible to call some code for each line of a nested
because that would damage the header of the encapsulated message

=item $obj-E<gt>B<stripSignature>(%options)

Inherited, see L<Mail::Message::Body::Construct/"Constructing a body">

=item $obj-E<gt>B<unify>($body)

Inherited, see L<Mail::Message::Body::Encode/"Constructing a body">

=back

=head2 The body

Extends L<"The body" in Mail::Message::Body|Mail::Message::Body/"The body">.
 
=over 4

=item $obj-E<gt>B<isDelayed>()

Inherited, see L<Mail::Message::Body/"The body">

=item $obj-E<gt>B<isMultipart>()

Inherited, see L<Mail::Message::Body/"The body">

=item $obj-E<gt>B<isNested>()

Inherited, see L<Mail::Message::Body/"The body">

=item $obj-E<gt>B<message>( [$message] )

Inherited, see L<Mail::Message::Body/"The body">

=item $obj-E<gt>B<partNumberOf>($part)

Inherited, see L<Mail::Message::Body/"The body">

=back

=head2 About the payload

Extends L<"About the payload" in Mail::Message::Body|Mail::Message::Body/"About the payload">.
 
=over 4

=item $obj-E<gt>B<charset>()

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<checked>( [BOOLEAN] )

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<contentId>( [STRING|$field] )

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<description>( [STRING|$field] )

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<disposition>( [STRING|$field] )

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<dispositionFilename>( [$directory] )

Inherited, see L<Mail::Message::Body::Encode/"About the payload">

=item $obj-E<gt>B<isBinary>()

Inherited, see L<Mail::Message::Body::Encode/"About the payload">

=item $obj-E<gt>B<isText>()

Inherited, see L<Mail::Message::Body::Encode/"About the payload">

=item $obj-E<gt>B<mimeType>()

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<nrLines>()

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<size>()

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<transferEncoding>( [STRING|$field] )

Inherited, see L<Mail::Message::Body/"About the payload">

=item $obj-E<gt>B<type>( [STRING|$field] )

Inherited, see L<Mail::Message::Body/"About the payload">

=back

=head2 Access to the payload

Extends L<"Access to the payload" in Mail::Message::Body|Mail::Message::Body/"Access to the payload">.
 
=over 4

=item $obj-E<gt>B<endsOnNewline>()

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<file>()

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<forNested>(CODE)

Execute the CODE for the nested message.  This returns a new
nested body object.  Returns C<undef> when the CODE returns C<undef>.

=item $obj-E<gt>B<lines>()

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<nested>()

Returns the L<Mail::Message::Part|Mail::Message::Part> message which is enclosed within
this body.

=item $obj-E<gt>B<print>( [$fh] )

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<printEscapedFrom>($fh)

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<string>()

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<stripTrailingNewline>()

Inherited, see L<Mail::Message::Body/"Access to the payload">

=item $obj-E<gt>B<write>(%options)

Inherited, see L<Mail::Message::Body/"Access to the payload">

=back

=head2 Internals

Extends L<"Internals" in Mail::Message::Body|Mail::Message::Body/"Internals">.
 
=over 4

=item $obj-E<gt>B<addTransferEncHandler>( $name, <$class|$object> )

=item Mail::Message::Body::Nested-E<gt>B<addTransferEncHandler>( $name, <$class|$object> )

Inherited, see L<Mail::Message::Body::Encode/"Internals">

=item $obj-E<gt>B<contentInfoFrom>($head)

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<contentInfoTo>($head)

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<fileLocation>( [$begin, $end] )

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<getTransferEncHandler>($type)

Inherited, see L<Mail::Message::Body::Encode/"Internals">

=item $obj-E<gt>B<isModified>()

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<load>()

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<modified>( [BOOLEAN] )

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<moveLocation>( [$distance] )

Inherited, see L<Mail::Message::Body/"Internals">

=item $obj-E<gt>B<read>( $parser, $head, $bodytype, [$chars, [$lines]] )

Inherited, see L<Mail::Message::Body/"Internals">

=back

=head2 Error handling

Extends L<"Error handling" in Mail::Message::Body|Mail::Message::Body/"Error handling">.
 
=over 4

=item $obj-E<gt>B<AUTOLOAD>()

Inherited, see L<Mail::Message::Body/"Error handling">

=item $obj-E<gt>B<addReport>($object)

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<defaultTrace>( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )

=item Mail::Message::Body::Nested-E<gt>B<defaultTrace>( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<errors>()

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<log>( [$level, [$strings]] )

=item Mail::Message::Body::Nested-E<gt>B<log>( [$level, [$strings]] )

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<logPriority>($level)

=item Mail::Message::Body::Nested-E<gt>B<logPriority>($level)

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<logSettings>()

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<notImplemented>()

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<report>( [$level] )

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<reportAll>( [$level] )

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<trace>( [$level] )

Inherited, see L<Mail::Reporter/"Error handling">

=item $obj-E<gt>B<warnings>()

Inherited, see L<Mail::Reporter/"Error handling">

=back

=head2 Cleanup

Extends L<"Cleanup" in Mail::Message::Body|Mail::Message::Body/"Cleanup">.
 
=over 4

=item $obj-E<gt>B<DESTROY>()

Inherited, see L<Mail::Reporter/"Cleanup">

=back

=head1 DETAILS

Extends L<"DETAILS" in Mail::Message::Body|Mail::Message::Body/"DETAILS">.
 
=head1 DIAGNOSTICS

=over 4

=item Warning: Charset $name is not known

The encoding or decoding of a message body encounters a character set which
is not understood by Perl's Encode module.

=item Warning: No decoder defined for transfer encoding $name.

The data (message body) is encoded in a way which is not currently understood,
therefore no decoding (or recoding) can take place.

=item Warning: No encoder defined for transfer encoding $name.

The data (message body) has been decoded, but the required encoding is
unknown.  The decoded data is returned.

=item 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.

=item Warning: Unknown line terminator $eol ignored

=item Error: You cannot use foreachLine on a nested

L<foreachLine()|Mail::Message::Body::Nested/"METHODS"> should be used on decoded message bodies only, because
it would modify the header of the encapsulated message. which is
clearly not acceptable.

=back

=head1 SEE ALSO

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

=head1 LICENSE

Copyrights 2001-2022 by [Mark Overmeer <markov@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 F<http://dev.perl.org/licenses/>