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.IX Title "Mail::Field 3"
.TH Mail::Field 3 2026-10-24 "perl v5.44.0" "User Contributed Perl Documentation"
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.nh
Mail::Field \- base\-class for manipulation of mail header fields
.PP
.Vb 1
\& use Mail::Field;
\&    
\& my $field = Mail::Field\->new(\*(AqSubject\*(Aq, \*(Aqsome subject text\*(Aq);
\& my $field = Mail::Field\->new(Subject => \*(Aqsome subject text\*(Aq);
\& print $field\->tag,": ",$field\->stringify,"\en";
\&
\& my $field = Mail::Field\->subject(\*(Aqsome subject text\*(Aq);
.Ve
.PP
\&\f(CW\*(C`Mail::Field\*(C'\fR creates and manipulates fields in MIME headers, collected
within a Mail::Header object.  Different field types have their
own sub\-class (extension), defining additional useful accessors to the
field content.
.PP
People are invited to merge their implementation to special fields into
MailTools, to maintain a consistent set of packages and documentation.
.PP
=c_method new \f(CW$tag\fR [, STRING | \f(CW%options\fR]
Create an object in the class which defines the field specified by
the \f(CW$tag\fR argument.
.PP
It is more clear to call either \fBstringify()\fR or \fBparse()\fR directly, because
this method does not add additional processing.
.PP
All sub\-classes should be called Mail::Field::\fIname\fR where \fIname\fR is
derived from the tag using these rules.
.IP \(bu 4
Consider a tag as being made up of elements separated by \*(Aq\-\*(Aq
.IP \(bu 4
Convert all characters to lowercase except the first in each element, which
should be uppercase.
.IP \(bu 4
\&\fIname\fR is then created from these elements by using the first
N characters from each element.
.IP \(bu 4
N is calculated by using the formula :\-
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\&    int((7 + #elements) / #elements)
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.IP \(bu 4
\&\fIname\fR is then limited to a maximum of 8 characters, keeping the first 8
characters.
.PP
For an example of this take a look at the definition of the 
\&\f(CW_header_pkg_name()\fR subroutine in \f(CW\*(C`Mail::Field\*(C'\fR
.SH "POD ERRORS"
.IX Header "POD ERRORS"
Hey! \fBThe above document had some coding errors, which are explained below:\fR
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