libmime-types-perl 2.14-1 / usr / share / perl5 / MIME / Type.pod

=encoding utf8

=head1 NAME

MIME::Type - description of one MIME type

=head1 SYNOPSIS

 use MIME::Types;
 my $mimetypes = MIME::Types->new;
 my MIME::Type $plaintext = $mimetypes->type('text/plain');
 print $plaintext->mediaType;   # text
 print $plaintext->subType;     # plain

 my @ext = $plaintext->extensions;
 print "@ext"                   # txt asc c cc h hh cpp

 print $plaintext->encoding     # 8bit
 if($plaintext->isBinary)       # false
 if($plaintext->isAscii)        # true
 if($plaintext->equals('text/plain') {...}
 if($plaintext eq 'text/plain') # same

 print MIME::Type->simplified('x-appl/x-zip') #  'appl/zip'

=head1 DESCRIPTION

MIME types are used in MIME entities, for instance as part of e-mail
and HTTP traffic.  Sometimes real knowledge about a mime-type is need.
Objects of C<MIME::Type> store the information on one such type.

=head1 OVERLOADED

=over 4

=item overload: B<string comparison>

When a MIME::Type object is compared to either a string or another
MIME::TYpe, the L<equals()|MIME::Type/"Knowledge"> method is called.  Comparison is smart,
which means that it extends common string comparison with some
features which are defined in the related RFCs.

=item overload: B<stringification>

The stringification (use of the object in a place where a string
is required) will result in the type name, the same as L<type()|MIME::Type/"Attributes">
returns.

example: use of stringification

 my $mime = MIME::Type->new('text/html');
 print "$mime\n";   # explicit stringification
 print $mime;       # implicit stringification

=back

=head1 METHODS

=head2 Initiation

=over 4

=item MIME::Type-E<gt>B<new>(%options)

Create (I<instantiate>) a new MIME::Type object which manages one
mime type.

 -Option    --Default
  encoding    <depends on type>
  extensions  []
  simplified  <derived from type>
  system      undef
  type        <required>

=over 2

=item encoding => '7bit'|'8bit'|'base64'|'quoted-printable'

How must this data be encoded to be transported safely.  The default
depends on the type: mimes with as main type C<text/> will default
to C<quoted-printable> and all other to C<base64>.

=item extensions => REF-ARRAY

An array of extensions which are using this mime.

=item simplified => STRING

The mime types main- and sub-label can both start with C<x->, to indicate
that is a non-registered name.  Of course, after registration this flag
can disappear which adds to the confusion.  The simplified string has the
C<x-> thingies removed and are translated to lower-case.

=item system => REGEX

Regular expression which defines for which systems this rule is valid.  The
REGEX is matched on C<$^O>.

=item type => STRING

The type which is defined here.  It consists of a I<type> and a I<sub-type>,
both case-insensitive.  This module will return lower-case, but accept
upper-case.

=back

=back

=head2 Attributes

=over 4

=item $obj-E<gt>B<encoding>()

Returns the type of encoding which is required to transport data of this
type safely.

=item $obj-E<gt>B<extensions>()

Returns a list of extensions which are known to be used for this
mime type.

=item $obj-E<gt>B<simplified>( [$string] )

=item MIME::Type-E<gt>B<simplified>( [$string] )

Returns the simplified mime type for this object or the specified STRING.
Mime type names can get officially registered.  Until then, they have to
carry an C<x-> preamble to indicate that.  Of course, after recognition,
the C<x-> can disappear.  In many cases, we prefer the simplified version
of the type.

example: results of simplified()

 my $mime = MIME::Type->new(type => 'x-appl/x-zip');
 print $mime->simplified;                     # 'appl/zip'

 print $mime->simplified('text/PLAIN');       # 'text/plain'
 print MIME::Type->simplified('x-xyz/x-abc'); # 'xyz/abc'

=item $obj-E<gt>B<system>()

Returns the regular expression which can be used to determine whether this
type is active on the system where you are working on.

=item $obj-E<gt>B<type>()

Returns the long type of this object, for instance C<'text/plain'>

=back

=head2 Knowledge

=over 4

=item $obj-E<gt>B<equals>($string|$mime)

Compare this mime-type object with a STRING or other object.  In case of
a STRING, simplification will take place.

=item $obj-E<gt>B<isAscii>()

Old name for L<isText()|MIME::Type/"Knowledge">.

=item $obj-E<gt>B<isBinary>()

Returns true when the type is not known to be text.  See L<isText()|MIME::Type/"Knowledge">.

=item $obj-E<gt>B<isExperimental>()

[2.00] Return C<true> when the type is defined for experimental
use; the subtype starts with C<x.>

=item $obj-E<gt>B<isPersonal>()

[2.00] Return C<true> when the type is defined by a person for
private use; the subtype starts with C<prs.>

=item $obj-E<gt>B<isRegistered>()

Mime-types which are not registered by IANA nor defined in RFCs shall
start with an C<x->.  This counts for as well the media-type as the
sub-type.  In case either one of the types starts with C<x-> this
method will return false.

=item $obj-E<gt>B<isSignature>()

Returns true when the type is in the list of known signatures.

=item $obj-E<gt>B<isText>()

[2.05] All types which may have the charset attribute, are text.  However,
there is currently no record of attributes in this module... so we guess.

=item $obj-E<gt>B<isVendor>()

[2.00] Return C<true> when the type is defined by a vendor; the subtype
starts with C<vnd.>

=item $obj-E<gt>B<mediaType>()

The media type of the simplified mime.
For C<'text/plain'> it will return C<'text'>.

For historical reasons, the C<'mainType'> method still can be used
to retrieve the same value.  However, that method is deprecated.

=item $obj-E<gt>B<subType>()

The sub type of the simplified mime.
For C<'text/plain'> it will return C<'plain'>.

=back

=head1 DIAGNOSTICS

=over 4

=item Error: Type parameter is obligatory.

When a L<MIME::Type|MIME::Type> object is created, the type itself must be
specified with the C<type> option flag.

=back

=head1 SEE ALSO

This module is part of MIME-Types distribution version 2.14,
built on November 08, 2017. Website: F<http://perl.overmeer.net/mimetypes/>

=head1 LICENSE

Copyrights 1999,2001-2017 by [Mark Overmeer]. For other contributors see ChangeLog.

This program is free software; you can redistribute it and/or modify it
under the Artistic license.
See F<http://dev.perl.org/licenses/artistic.html>