197 lines
4.9 KiB
Plaintext
197 lines
4.9 KiB
Plaintext
|
=encoding utf8
|
||
|
|
|
||
|
|
=head1 NAME
|
||
|
|
|
||
|
|
Mail::Field - base-class for manipulation of mail header fields
|
||
|
|
|
||
|
|
=head1 INHERITANCE
|
||
|
|
|
||
|
|
Mail::Field is extended by
|
||
|
|
Mail::Field::AddrList
|
||
|
|
Mail::Field::Date
|
||
|
|
Mail::Field::Generic
|
||
|
|
|
||
|
|
=head1 SYNOPSIS
|
||
|
|
|
||
|
|
use Mail::Field;
|
||
|
|
|
||
|
|
my $field = Mail::Field->new('Subject', 'some subject text');
|
||
|
|
my $field = Mail::Field->new(Subject => 'some subject text');
|
||
|
|
print $field->tag,": ",$field->stringify,"\n";
|
||
|
|
|
||
|
|
my $field = Mail::Field->subject('some subject text');
|
||
|
|
|
||
|
|
=head1 DESCRIPTION
|
||
|
|
|
||
|
|
C<Mail::Field> creates and manipulates fields in MIME headers, collected
|
||
|
|
within a L<Mail::Header|Mail::Header> object. Different field types have their
|
||
|
|
own sub-class (extension), defining additional useful accessors to the
|
||
|
|
field content.
|
||
|
|
|
||
|
|
People are invited to merge their implementation to special fields into
|
||
|
|
MailTools, to maintain a consistent set of packages and documentation.
|
||
|
|
|
||
|
|
=head1 METHODS
|
||
|
|
|
||
|
|
=head2 Constructors
|
||
|
|
|
||
|
|
Mail::Field (and it's sub-classes) define several methods which return
|
||
|
|
new objects. These can all be categorized as constructor.
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item Mail::Field-E<gt>B<combine>($fields)
|
||
|
|
|
||
|
|
Take a LIST of C<Mail::Field> objects (which should all be of the same
|
||
|
|
sub-class) and create a new object in that same class.
|
||
|
|
|
||
|
|
=item Mail::Field-E<gt>B<extract>( $tag, $head [, $index ] )
|
||
|
|
|
||
|
|
Takes as arguments the tag name, a C<Mail::Head> object
|
||
|
|
and optionally an index.
|
||
|
|
|
||
|
|
If the index argument is given then C<extract> will retrieve the given tag
|
||
|
|
from the C<Mail::Head> object and create a new C<Mail::Field> based object.
|
||
|
|
I<undef> will be returned in the field does not exist.
|
||
|
|
|
||
|
|
If the index argument is not given the result depends on the context
|
||
|
|
in which C<extract> is called. If called in a scalar context the result
|
||
|
|
will be as if C<extract> was called with an index value of zero. If called
|
||
|
|
in an array context then all tags will be retrieved and a list of
|
||
|
|
C<Mail::Field> objects will be returned.
|
||
|
|
|
||
|
|
=item Mail::Field-E<gt>B<new>( $tag [, STRING | %options] )
|
||
|
|
|
||
|
|
Create an object in the class which defines the field specified by
|
||
|
|
the $tag argument.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
=head2 "Fake" constructors
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<create>(%options)
|
||
|
|
|
||
|
|
This constructor is used internally with preprocessed field information.
|
||
|
|
When called on an existing object, its original content will get
|
||
|
|
replaced.
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<parse>()
|
||
|
|
|
||
|
|
Parse a field line.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
=head2 Accessors
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<set>(%options)
|
||
|
|
|
||
|
|
Change the settings (the content, but then smart) of this field.
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<stringify>()
|
||
|
|
|
||
|
|
Returns the field as a string.
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<tag>()
|
||
|
|
|
||
|
|
=item Mail::Field-E<gt>B<tag>()
|
||
|
|
|
||
|
|
Return the tag (in the correct case) for this item. Well, actually any
|
||
|
|
casing is OK, because the field tags are treated case-insensitive; however
|
||
|
|
people have some preferences.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
=head2 Smart accessors
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item $obj-E<gt>B<text>( [STRING] )
|
||
|
|
|
||
|
|
Without arguments, the field is returned as L<stringify()|Mail::Field/"Accessors"> does. Otherwise,
|
||
|
|
the STRING is parsed with L<parse()|Mail::Field/""Fake" constructors"> to replace the object's content.
|
||
|
|
|
||
|
|
It is more clear to call either L<stringify()|Mail::Field/"Accessors"> or L<parse()|Mail::Field/""Fake" constructors"> directly, because
|
||
|
|
this method does not add additional processing.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
=head1 DETAILS
|
||
|
|
|
||
|
|
=head2 SUB-CLASS PACKAGE NAMES
|
||
|
|
|
||
|
|
All sub-classes should be called Mail::Field::I<name> where I<name> is
|
||
|
|
derived from the tag using these rules.
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item *
|
||
|
|
|
||
|
|
Consider a tag as being made up of elements separated by '-'
|
||
|
|
|
||
|
|
=item *
|
||
|
|
|
||
|
|
Convert all characters to lowercase except the first in each element, which
|
||
|
|
should be uppercase.
|
||
|
|
|
||
|
|
=item *
|
||
|
|
|
||
|
|
I<name> is then created from these elements by using the first
|
||
|
|
N characters from each element.
|
||
|
|
|
||
|
|
=item *
|
||
|
|
|
||
|
|
N is calculated by using the formula :-
|
||
|
|
|
||
|
|
int((7 + #elements) / #elements)
|
||
|
|
|
||
|
|
=item *
|
||
|
|
|
||
|
|
I<name> is then limited to a maximum of 8 characters, keeping the first 8
|
||
|
|
characters.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
For an example of this take a look at the definition of the
|
||
|
|
C<_header_pkg_name()> subroutine in C<Mail::Field>
|
||
|
|
|
||
|
|
=head1 DIAGNOSTICS
|
||
|
|
|
||
|
|
=over 4
|
||
|
|
|
||
|
|
=item Error: Undefined subroutine <method> called
|
||
|
|
|
||
|
|
Mail::Field objects use autoloading to compile new functionality.
|
||
|
|
Apparently, the method called is not implemented for the specific
|
||
|
|
class of the field object.
|
||
|
|
|
||
|
|
=back
|
||
|
|
|
||
|
|
=head1 SEE ALSO
|
||
|
|
|
||
|
|
This module is part of the MailTools distribution,
|
||
|
|
F<http://perl.overmeer.net/mailtools/>.
|
||
|
|
|
||
|
|
=head1 AUTHORS
|
||
|
|
|
||
|
|
The MailTools bundle was developed by Graham Barr. Later, Mark
|
||
|
|
Overmeer took over maintenance without commitment to further development.
|
||
|
|
|
||
|
|
Mail::Cap by Gisle Aas E<lt>aas@oslonett.noE<gt>.
|
||
|
|
Mail::Field::AddrList by Peter Orbaek E<lt>poe@cit.dkE<gt>.
|
||
|
|
Mail::Mailer and Mail::Send by Tim Bunce E<lt>Tim.Bunce@ig.co.ukE<gt>.
|
||
|
|
For other contributors see ChangeLog.
|
||
|
|
|
||
|
|
=head1 LICENSE
|
||
|
|
|
||
|
|
Copyrights 1995-2000 Graham Barr E<lt>gbarr@pobox.comE<gt> and
|
||
|
|
2001-2017 Mark Overmeer E<lt>perl@overmeer.netE<gt>.
|
||
|
|
|
||
|
|
This program is free software; you can redistribute it and/or modify it
|
||
|
|
under the same terms as Perl itself.
|
||
|
|
See F<http://www.perl.com/perl/misc/Artistic.html>
|
||
|
|
|