Provided by: libmail-message-perl_3.019-1_all 
NAME
Mail::Message::Field::Full - construct one smart line in a message header
INHERITANCE
Mail::Message::Field::Full
is a Mail::Message::Field
is a Mail::Reporter
Mail::Message::Field::Full is extended by
Mail::Message::Field::Structured
Mail::Message::Field::Unstructured
SYNOPSIS
# Getting to understand the complexity of a header field ...
my $fast = $msg->head->get('subject');
my $full = Mail::Message::Field::Full->from($fast);
my $full = $msg->head->get('subject')->study; # same
my $full = $msg->head->study('subject'); # same
my $full = $msg->study('subject'); # same
# ... or build a complex header field yourself
my $f = Mail::Message::Field::Full->new('To');
my $f = Mail::Message::Field::Full->new('Subject: hi!');
my $f = Mail::Message::Field::Full->new(Subject => 'hi!');
DESCRIPTION
This is the full implementation of a header field: it has full understanding of all predefined header
fields. These objects will be quite slow, because header fields can be very complex. Of course, this
class delivers the optimal result, but for a quite large penalty in performance and memory consumption.
Are you willing to accept?
This class supports the common header description from RFC2822 (formerly RFC822), the extensions with
respect to character set encodings as specified in RFC2047, and the extensions on language specification
and long parameter wrapping from RFC2231. If you do not need the latter two, then the
Mail::Message::Field::Fast and Mail::Message::Field::Flex are enough for your application.
RFC5322 (<https://www.rfc-editor.org/rfc/rfc5322.html>) describes a long list of obsolete syntax for
structured header fields. This mainly refers to disallowing white-spaces and folding on many
inconvenient locations. This matches MailBox's natural behavior.
Extends "DESCRIPTION" in Mail::Message::Field.
OVERLOADED
Extends "OVERLOADED" in Mail::Message::Field.
overload: "" stringification
In string context, the decoded body is returned, as if decodedBody() would have been called.
Improves base, see "OVERLOADED" in Mail::Message::Field
overload: 0+ numification
Inherited, see "OVERLOADED" in Mail::Message::Field
overload: <=> numeric comparison
Inherited, see "OVERLOADED" in Mail::Message::Field
overload: bool boolean
Inherited, see "OVERLOADED" in Mail::Message::Field
overload: cmp string comparison
Inherited, see "OVERLOADED" in Mail::Message::Field
METHODS
Extends "METHODS" in Mail::Message::Field.
Constructors
Extends "Constructors" in Mail::Message::Field.
$obj->clone()
Inherited, see "Constructors" in Mail::Message::Field
$class->from($field, %options)
Convert any $field (a Mail::Message::Field object) into a new Mail::Message::Field::Full object.
This conversion is done the hard way: the string which is produced by the original object is parsed
again. Usually, the string which is parsed is exactly the line (or lines) as found in the original
input source, which is a good thing because Full fields are much more careful with the actual
content.
%options are passed to the constructor (see new()). In any case, some extensions of this Full field
class is returned. It depends on which field is created what kind of class we get.
» example:
my $fast = $msg->head->get('subject');
my $full = Mail::Message::Field::Full->from($fast);
my $full = $msg->head->get('subject')->study; # same
my $full = $msg->head->study('subject'); # same
my $full = $msg->get('subject'); # same
$class->new(($line | $name, [$body], @attributes), %options)
Creating a new field object the correct way is a lot of work, because there is so much freedom in the
RFCs, but at the same time so many restrictions. Most fields are implemented, but if you have your
own field (and do no want to contribute it to MailBox), then simply call new on your own package.
You have the choice to instantiate the object as string or in prepared parts:
• new($line, %options)
Pass a $line as it could be found in a file: a (possibly folded) line which is terminated by a
new-line.
• new($name, [$body], @attributes, %options)
A set of values which shape the line.
The $name is a wellformed header name (you may use wellformedName()) to be sure about the casing.
The $body is a string, one object, or an ARRAY of objects. In case of objects, they must fit to the
constructor of the field: the types which are accepted may differ. The optional ATTRIBUTE list
contains Mail::Message::Field::Attribute objects. Finally, there are some OPTIONS. Improves base,
see "Constructors" in Mail::Message::Field
-Option --Defined in --Default
charset undef
encoding 'q'
force false
language undef
log Mail::Reporter 'WARNINGS'
trace Mail::Reporter 'WARNINGS'
charset => $charset
The body is specified in UTF-8, and must become 7-bits ascii to be transmited. Specify a $charset
to which the multi-byte utf8 is converted before it gets encoded. See encode(), which does the
job.
encoding => 'q'|'Q'|'b'|'B'
Non-ascii characters are encoded using Quoted-Printable ('q' or 'Q') or Base64 ('b' or 'B')
encoding.
force => BOOLEAN
Enforce encoding in the specified charset, even when it is not needed because the body does not
contain any non-ascii characters.
language => $language
The $language used can be specified, however is rarely used my mail clients.
log => LEVEL
trace => LEVEL
» example:
my $s = Mail::Message::Field::Full->new('Subject: Hello World');
my $s = Mail::Message::Field::Full->new('Subject', 'Hello World');
my @attrs = (Mail::Message::Field::Attribute->new(...), ...);
my @options = (extra => 'the color blue');
my $t = Mail::Message::Field::Full->new(To => \@addrs, @attrs, @options);
Attributes
Extends "Attributes" in Mail::Message::Field.
$obj->logSettings()
Inherited, see "Attributes" in Mail::Reporter
The field
Extends "The field" in Mail::Message::Field.
$any->isStructured()
Inherited, see "The field" in Mail::Message::Field
$obj->length()
Inherited, see "The field" in Mail::Message::Field
$obj->nrLines()
Inherited, see "The field" in Mail::Message::Field
$obj->print( [$fh] )
Inherited, see "The field" in Mail::Message::Field
$obj->size()
Inherited, see "The field" in Mail::Message::Field
$obj->string( [$wrap] )
Inherited, see "The field" in Mail::Message::Field
$obj->toDisclose()
Inherited, see "The field" in Mail::Message::Field
Access to the name
Extends "Access to the name" in Mail::Message::Field.
$obj->Name()
Inherited, see "Access to the name" in Mail::Message::Field
$obj->name()
Inherited, see "Access to the name" in Mail::Message::Field
$obj->wellformedName( [STRING] )
Inherited, see "Access to the name" in Mail::Message::Field
Access to the body
Extends "Access to the body" in Mail::Message::Field.
$obj->body()
Inherited, see "Access to the body" in Mail::Message::Field
$obj->decodedBody(%options)
Returns the unfolded body of the field, where encodings are resolved. The returned line will still
contain comments and such. The %options are passed to the decoder, see decode().
BE WARNED: if the field is a structured field, the content may change syntax, because of encapsulated
special characters. By default, the body is decoded as text, which results in a small difference
within comments as well (read the RFC).
$obj->folded()
Inherited, see "Access to the body" in Mail::Message::Field
$obj->foldedBody( [$body] )
Inherited, see "Access to the body" in Mail::Message::Field
$any->stripCFWS( [STRING] )
Inherited, see "Access to the body" in Mail::Message::Field
$obj->unfoldedBody( [$body, [$wrap]] )
Inherited, see "Access to the body" in Mail::Message::Field
Access to the content
Extends "Access to the content" in Mail::Message::Field.
$obj->addresses()
Inherited, see "Access to the content" in Mail::Message::Field
$obj->attribute( $name, [$value] )
Inherited, see "Access to the content" in Mail::Message::Field
$obj->attributes()
Inherited, see "Access to the content" in Mail::Message::Field
$obj->beautify()
For structured header fields, this removes the original encoding of the field's body (the format as
it was offered to parse()), therefore the next request for the field will have to re-produce the read
data clean and nice. For unstructured bodies, this method doesn't do a thing.
$obj->comment( [STRING] )
Inherited, see "Access to the content" in Mail::Message::Field
$any->createComment(STRING, %options)
Create a comment to become part in a field. Comments are automatically included within parenthesis.
Matching pairs of parenthesis are permitted within the "STRING". When a non-matching parenthesis are
used, it is only permitted with an escape (a backslash) in front of them. These backslashes will be
added automatically if needed (don't worry!). Backslashes will stay, except at the end, where it
will be doubled.
The %options are "charset", "language", and "encoding" as always. The created comment is returned.
$any->createPhrase(STRING, %options)
A phrase is a text which plays a well defined role. This is the main difference with comments, which
have do specified meaning. Some special characters in the phrase will cause it to be surrounded with
double quotes: do not specify them yourself.
The %options are "charset", "language", and "encoding", as always.
$obj->study()
Inherited, see "Access to the content" in Mail::Message::Field
$any->toDate( [$time] )
Inherited, see "Access to the content" in Mail::Message::Field
$obj->toInt()
Inherited, see "Access to the content" in Mail::Message::Field
Other methods
Extends "Other methods" in Mail::Message::Field.
$any->dateToTimestamp(STRING)
Inherited, see "Other methods" in Mail::Message::Field
Internals
Extends "Internals" in Mail::Message::Field.
$obj->consume( $line | <$name,<$body|$objects>> )
Inherited, see "Internals" in Mail::Message::Field
$any->decode(STRING, %options)
Decode field encoded "STRING" to an utf8 string. The input "STRING" is part of a header field, and
as such, may contain encoded words in "=?...?.?...?=" format defined by RFC2047. The "STRING" may
contain multiple encoded parts, maybe using different character sets.
Be warned: you MUST first interpret the field into parts, like phrases and comments, and then decode
each part separately, otherwise the decoded text may interfere with your markup characters.
Be warned: language information, which is defined in RFC2231, is ignored.
Encodings with unknown charsets are left untouched [requires v2.085, otherwise croaked]. Unknown
characters within an charset are replaced by a '?'.
-Option --Default
is_text true
is_text => BOOLEAN
Encoding on text is slightly more complicated than encoding structured data, because it contains
blanks. Visible blanks have to be ignored between two encoded words in the text, but not when an
encoded word follows or precedes an unencoded word. Phrases and comments are texts.
» example:
print Mail::Message::Field::Full->decode('=?iso-8859-1?Q?J=F8rgen?=');
# prints JE<0slash>rgen
$obj->defaultWrapLength( [$length] )
Inherited, see "Internals" in Mail::Message::Field
$obj->encode(STRING, %options)
Encode the (possibly utf8 encoded) "STRING" to a string which is acceptable to the RFC2047 definition
of a header: only containing us-ascii characters.
-Option --Default
charset 'us-ascii'
encoding 'q'
force false
language undef
name undef
charset => STRING
"STRING" is an utf8 string which has to be translated into any byte-wise character set for
transport, because MIME-headers can only contain ascii characters.
encoding => 'q'|'Q'|'b'|'B'
The character encoding to be used. With "q" or "Q", quoted-printable encoding will be used. With
"b " or "B ", base64 encoding will be taken.
force => BOOLEAN
Encode the string, even when it only contains us-ascii characters. By default, this is off because
it decreases readibility of the produced header fields.
language => STRING
RFC2231 defines how to specify language encodings in encoded words. The "STRING" is a strandard
iso language name.
name => STRING
[3.002] When the name of the field is given, the first encoded line will be shorter.
$any->fold( $name, $body, [$maxchars] )
Inherited, see "Internals" in Mail::Message::Field
$obj->setWrapLength( [$length] )
Inherited, see "Internals" in Mail::Message::Field
$obj->stringifyData(STRING|ARRAY|$objects)
Inherited, see "Internals" in Mail::Message::Field
$obj->unfold(STRING)
Inherited, see "Internals" in Mail::Message::Field
Parsing
You probably do not want to call these parsing methods yourself: use the standard constructors (new())
and it will be done for you.
$any->consumeComment(STRING)
Try to read a comment from the "STRING". When successful, the comment without encapsulating
parenthesis is returned, together with the rest of the string.
$obj->consumeDotAtom(STRING)
Returns three elemens: the atom-text, the rest string, and the concatenated comments. Both atom and
comments can be "undef".
$any->consumePhrase(STRING)
Take the "STRING", and try to strip-off a valid phrase. In the obsolete phrase syntax, any sequence
of words is accepted as phrase (as long as certain special characters are not used). RFC2822 is
stricter: only one word or a quoted string is allowed. As always, the obsolete syntax is accepted,
and the new syntax is produced.
This method returns two elements: the phrase (or "undef") followed by the resulting string. The
phrase will be removed from the optional quotes. Be warned that "" will return an empty, valid
phrase.
» example:
my ($phrase, $rest) = $field->consumePhrase( q["hi!" <sales@example.com>] );
$obj->parse(STRING)
Get the detailed information from the "STRING", and store the data found in the field object. The
accepted input is very field type dependent. Unstructured fields do no parsing whatsoever.
$obj->produceBody()
Produce the text for the field, based on the information stored within the field object.
Usually, you wish the exact same line as was found in the input source of a message. But when you
have created a field yourself, it should get formatted. You may call beautify() on a preformatted
field to enforce a call to this method when the field is needed later.
Error handling
Extends "Error handling" in Mail::Message::Field.
$obj->AUTOLOAD()
Inherited, see "Error handling" in Mail::Reporter
$obj->addReport($object)
Inherited, see "Error handling" in Mail::Reporter
$any->defaultTrace( [$level]|[$loglevel, $tracelevel]|[$level, $callback] )
Inherited, see "Error handling" in Mail::Reporter
$obj->errors()
Inherited, see "Error handling" in Mail::Reporter
$any->log( [$level, [$strings]] )
Inherited, see "Error handling" in Mail::Reporter
$any->logPriority($level)
Inherited, see "Error handling" in Mail::Reporter
$obj->notImplemented()
Inherited, see "Error handling" in Mail::Reporter
$obj->report( [$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::Message::Field.
$obj->DESTROY()
Inherited, see "Cleanup" in Mail::Reporter
DETAILS
Extends "DETAILS" in Mail::Message::Field.
DIAGNOSTICS
Warning: Field content is not numerical: $content
The numeric value of a field is requested (for instance the "Lines" or "Content-Length" fields should
be numerical), however the data contains weird characters. Cast by toInt()
Error: Field name too long (max $length), in '$name'
It is not specified in the RFCs how long a field name can be, but at least it should be a few
characters shorter than the line wrap. Cast by fold()
Warning: Illegal character in charset '$charset'
The field is created with an utf8 string which only contains data from the specified character set.
However, that character set can never be a valid name because it contains characters which are not
permitted. Cast by encode()
Warning: Illegal character in field name $name
A new field is being created which does contain characters not permitted by the RFCs. Using this
field in messages may break other e-mail clients or transfer agents, and therefore mutulate or
extinguish your message. Cast by consume()
Warning: Illegal character in language '$lang'
The field is created with data which is specified to be in a certain language, however, the name of
the language cannot be valid: it contains characters which are not permitted by the RFCs. Cast by
encode()
Warning: Illegal encoding '$encoding', used 'q'
The RFCs only permit base64 ("b " or "B ") or quoted-printable ("q" or "Q") encoding. Other than
these four options are illegal. Cast by encode()
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. Cast by notImplemented()
SEE ALSO
This module is part of Mail-Message version 3.019, built on November 24, 2025. Website:
http://perl.overmeer.net/CPAN/
LICENSE
For contributors see file ChangeLog.
This software is copyright (c) 2001-2025 by Mark Overmeer.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5
programming language system itself.
perl v5.40.1 2025-12-07 Mail::Message::Field::Full(3pm)