Mail::Message::Field::UseriContributed Perl Mail::Message::Field::Attribute(3)NAMEMail::Message::Field::Attribute - one attribute of a full field
INHERITANCEMail::Message::Field::Attribute
is a Mail::Reporter
SYNOPSIS
my $field = $msg->head->get('Content-Disposition') or return;
my $full = $field->study; # full understanding in unicode
my $filename = $full->attribute('filename') or return;
print ref $filename; # this class name
print $filename; # the attributes content in utf-8
print $filename->value; # same
print $filename->string; # print string as was found in the file
$filename->print(\*OUT); # print as was found in the file
DESCRIPTION
Attributes within MIME fields can be quite complex, and therefore be
slow and consumes a lot of memory. The Mail::Message::Field::Fast and
Mail::Message::Field::Flex simplify them the attributes a lot, which
may result in erroneous behavior in rare cases. With the increase of
non-western languages on Internet, the need for the complex headers
becomes more and more in demand.
A "Mail::Message::Field::Attribute" can be found in any structured
Mail::Message::Field::Full header field.
METHODS
Constructors
Mail::Message::Field::Attribute->new((NAME, [VALUE] | STRING), OPTIONS)
Create a new attribute NAME with the optional VALUE. If no VALUE
is specified, the first argument of this method is inspected for an
equals sign '='. If that character is present, the argument is
taken as STRING, containing a preformatted attribute which is
processed. Otherwise, the argument is taken as name without VALUE:
set the value later with value().
Whether encoding takes place depends on the OPTIONS and the
existence of non-ascii characters in the VALUE. The NAME can only
contain ascii characters, hence is never encoded.
To speed things up, attributes are not derived from the
Mail::Reporter base-class.
Option --Defined in --Default
charset 'us-ascii'
language undef
log Mail::Reporter 'WARNINGS'
trace Mail::Reporter 'WARNINGS'
use_continuations <true>
. charset => STRING
The VALUE is translated from utf-8 (Perl internal) to this
character set, and the resulting string is encoded if required.
"us-ascii" is the normal encoding for e-mail. Valid character
sets can be found with Encode::encodings(':all').
. language => STRING
RFC2231 adds the possiblity to specify a language with the
field. When no language is specified, none is included in the
encoding. Valid language names are defined by RFC2130. This
module has only limited support for this feature.
. log => LEVEL
. trace => LEVEL
. use_continuations => BOOLEAN
Continuations are used to break-up long parameters into pieces
which are no longer than 76 characters. Encodings are specified
in RFC2231, but not supported by some Mail User Agents.
example:
my $fn = Mail::Message::Field::Attribute
->new(filename => 'xyz');
my $fattr = 'Mail::Message::Field::Attribute'; # abbrev
my $fn = $fattr->new
( filename => "Re\xC7u"
, charset => 'iso-8859-15'
, language => 'nl-BE'
);
print $fn;
# --> filename*=iso-8859-15'nl-BE'Re%C7u
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::Field::Attribute->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::Field::Attribute->log([LEVEL [,STRINGS]])
See "Error handling" in Mail::Reporter
$obj->logPriority(LEVEL)
Mail::Message::Field::Attribute->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
The attribute
$obj->addComponent(STRING)
A component is a parameter as defined by RFC2045, optionally using
encoding or continuations as defined by RFC2231. Components of an
attribute are found when a field is being parsed. The RFCs are
very strict on valid characters, but we cannot be: you have to
accept what is coming in if you can.
example:
my $param = Mail::Message::Field::Attribute->new;
$param->addComponent("filename*=iso10646'nl-BE'%Re\47u");
$obj->charset
Returns the character set which is used for this parameter. If any
component is added which contains character set information, this
is directly available. Be warned that a character-set is case
insensitive.
$obj->language
Returns the language which is defined in the argument. If no
language is defined "undef" is returned, which should be
interpreted as "ANY"
$obj->name
Returns the name of this attribute.
$obj->string
Returns the parameter as reference to an array of lines. When only
one line is returned, it may be short enough to fit on the same
line with other components of the header field.
$obj->value([STRING])
Returns the value of this parameter, optionally after setting it
first.
Attribute encoding
$obj->decode
Translate all known continuations into a value. The produced value
is returned and may be utf-8 encoded or a plain string.
$obj->encode
Internals
$obj->mergeComponent(ATTRIBUTE)
Merge the components from the specified attribute in this
attribute. This is needed when components of the same attribute
are created separately. Merging is required by the field parsing.
DIAGNOSTICS
Warning: Illegal character in parameter name '$name'
The specified parameter name contains characters which are not
permitted by the RFCs. You can better change the name into
something which is accepted, or risk applications to corrupt or
ignore the message.
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.
Error: Too late to merge: value already changed.
SEE ALSO
This module is part of Mail-Box distribution version 2.094, built on
April 06, 2010. Website: http://perl.overmeer.net/mailbox/
LICENSE
Copyrights 2001-2010 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
perl v5.10.12010-04-06Mail::Message::Field::Attribute(3)
