Provided by: libmail-box-perl_2.110-1_all 
NAME
Mail::Message::Field::Attribute - one attribute of a full field
INHERITANCE
Mail::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.
See documentation in the base class.
OVERLOADED
overload: comparison()
When the second argument is a field, then both attribute name (case-sensitive) and the
decoded value must be the same. Otherwise, the value is compared.
overload: stringification()
Returns the decoded content of the attribute.
METHODS
See documentation in the base class.
Constructors
See documentation in the base class.
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
See documentation in the base class.
$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
See documentation in the base class.
$obj->DESTROY()
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
$obj->mergeComponent(ATTRIBUTE)
Merge the components from the specified attribute into this attribute. This is needed
when components of the same attribute are created separately. Merging is required by
the field parsing.
DIAGNOSTICS
Warning: Illegal character in parameter name '$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 2.110, built on January 05, 2014.
Website: http://perl.overmeer.net/mailbox/
LICENSE
Copyrights 2001-2014 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