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Mail::Message::Field::User(Contributed Perl DocMail::Message::Field::Full(3pm)

       Mail::Message::Field::Full - construct one smart line in a message

          is a Mail::Message::Field
          is a Mail::Reporter

        Mail::Message::Field::Full is extended by

        !! The details of this module are NOT FINISHED yet
        !! Most parts are already usable, however.  With care!

        # 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->get('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!');

       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.

       overload: ""

           See "OVERLOADED" in Mail::Message::Field

       overload: +0

           See "OVERLOADED" in Mail::Message::Field

       overload: <&lt;=>

           See "OVERLOADED" in Mail::Message::Field

       overload: bool

           See "OVERLOADED" in Mail::Message::Field

       overload: cmp

           See "OVERLOADED" in Mail::Message::Field

       overload: stringification

           In string context, the decoded body is returned, as if
           decodedBody() would have been called.



           See "Constructors" in Mail::Message::Field

       Mail::Message::Field::Full->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 carefull 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.


            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


           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:

           o   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.

           o   new NAME, [BODY], 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 ref-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

            Option  --Defined in     --Default
            charset                    undef
            encoding                   'q'
            force                      false
            language                   undef
            log       Mail::Reporter   'WARNINGS'
            trace     Mail::Reporter   'WARNINGS'

           . charset => STRING

               The body is specified in utf8, 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

           . language => STRING

               The language used can be specified, however is rarely used my
               mail clients.

           . log => LEVEL

           . trace => LEVEL


            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);

       The field



           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field


           See "The field" in Mail::Message::Field

       Access to the name


           See "Access to the name" in Mail::Message::Field


           See "Access to the name" in Mail::Message::Field


           See "Access to the name" in Mail::Message::Field

       Access to the body


           See "Access to the body" in Mail::Message::Field


           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).


           See "Access to the body" in Mail::Message::Field


           See "Access to the body" in Mail::Message::Field



           See "Access to the body" in Mail::Message::Field

       $obj->unfoldedBody([BODY, [WRAP]])

           See "Access to the body" in Mail::Message::Field

       Access to the content


           See "Access to the content" in Mail::Message::Field

       $obj->attribute(NAME [, VALUE])

           See "Access to the content" in Mail::Message::Field


           See "Access to the content" in Mail::Message::Field


           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.


           See "Access to the content" in Mail::Message::Field

       $obj->createComment(STRING, OPTIONS)

       Mail::Message::Field::Full->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.

       $obj->createPhrase(STRING, OPTIONS)

       Mail::Message::Field::Full->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.


           See "Access to the content" in Mail::Message::Field



           See "Access to the content" in Mail::Message::Field


           See "Access to the content" in Mail::Message::Field

       Other methods



           See "Other methods" in Mail::Message::Field


       $obj->consume(LINE | (NAME,BODY|OBJECTS))

           See "Internals" in Mail::Message::Field

       $obj->decode(STRING, OPTIONS)

       Mail::Message::Field::Full->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

           Be warned: language information, which is defined in RFC2231, is

            Option --Default
            is_text  1

           . 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 preceeds an unencoded word.
               Phrases and comments are texts.


            print Mail::Message::Field::Full->decode('=?iso-8859-1?Q?J=F8rgen?=');
               # prints   JE<0slash>rgen


           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     <flase>
            language  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.

       $obj->fold(NAME, BODY, [MAXCHARS])

       Mail::Message::Field::Full->fold(NAME, BODY, [MAXCHARS])

           See "Internals" in Mail::Message::Field


           See "Internals" in Mail::Message::Field


           See "Internals" in Mail::Message::Field


           See "Internals" in Mail::Message::Field




           Try to read a comment from the STRING.  When successful, the
           comment without encapsulation parenthesis is returned, together
           with the rest of the string.


           Returns three elemens: the atom-text, the rest string, and the
           concatenated comments.  Both atom and comments can be undef.



           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).  RFC2882 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.


            my ($phrase, $rest) = $field->consumePhrase( q["hi!" <salesATexample.com>] );


           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.


           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

       Error handling


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter

       $obj->defaultTrace([LEVEL]|[LOGLEVEL, TRACELEVEL]|[LEVEL, CALLBACK])


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter

       $obj->log([LEVEL [,STRINGS]])

       Mail::Message::Field::Full->log([LEVEL [,STRINGS]])

           See "Error handling" in Mail::Reporter



           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter


           See "Error handling" in Mail::Reporter



           See "Cleanup" in Mail::Reporter


           See "Cleanup" in Mail::Reporter

       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.

       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

       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.

       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.

       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.

       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.

       This module is part of Mail-Box distribution version 2.082, built on
       April 28, 2008. Website: http://perl.overmeer.net/mailbox/

       Copyrights 2001-2008 by Mark Overmeer. For other contributors see

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.  See

perl v5.10.0                      2008-04-28   Mail::Message::Field::Full(3pm)