pod::simple::subclassing.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

.Sp
.Vb 3
\&  <L content\-implicit="yes" to="http://www.perl.com/CPAN/authors/" type="url">
\&    http://www.perl.com/CPAN/authors/
\&  </L>
.Ve
.Sp
When a L<\fImanpage(section)\fR> code is parsed (and these are
fairly rare and not terribly useful), it produces this event structure:
.Sp
.Vb 3
\&  <L content\-implicit="yes" to="manpage(section)" type="man">
\&    manpage(section)
\&  </L>
.Ve
.Sp
The \f(CW\*(C`type="man"\*(C'\fR attribute is always specified for this type of
L code.
.Sp
For example, this Pod source:
.Sp
.Vb 1
\&  L<crontab(5)>
.Ve
.Sp
produces this event structure:
.Sp
.Vb 3
\&  <L content\-implicit="yes" to="crontab(5)" type="man">
\&    crontab(5)
\&  </L>
.Ve
.Sp
In the rare cases where a man page link has a specified, that text appears
in a \fIsection\fR attribute. For example, this Pod source:
.Sp
.Vb 1
\&  L<crontab(5)/"ENVIRONMENT">
.Ve
.Sp
will produce this event structure:
.Sp
.Vb 3
\&  <L content\-implicit="yes" section="ENVIRONMENT" to="crontab(5)" type="man">
\&    "ENVIRONMENT" in crontab(5)
\&  </L>
.Ve
.Sp
In the rare case where the Pod document has code like
L<\fIsometext\fR|\fImanpage(section)\fR>, then the \fIsometext\fR will appear
as the content of the element, the \fImanpage(section)\fR text will appear
only as the value of the \fIto\fR attribute, and there will be no
\&\f(CW\*(C`content\-implicit="yes"\*(C'\fR attribute (whose presence means that the Pod parser
had to infer what text should appear as the link text \*(-- as opposed to
cases where that attribute is absent, which means that the Pod parser did
\&\fInot\fR have to infer the link text, because that L code explicitly specified
some link text.)
.Sp
For example, this Pod source:
.Sp
.Vb 1
\&  L<hell itself!|crontab(5)>
.Ve
.Sp
will produce this event structure:
.Sp
.Vb 3
\&  <L to="crontab(5)" type="man">
\&    hell itself!
\&  </L>
.Ve
.Sp
The last type of L structure is for links to/within Pod documents. It is
the most complex because it can have a \fIto\fR attribute, \fIor\fR a
\&\fIsection\fR attribute, or both. The \f(CW\*(C`type="pod"\*(C'\fR attribute is always
specified for this type of L code.
.Sp
In the most common case, the simple case of a L<podpage> code
produces this event structure:
.Sp
.Vb 3
\&  <L content\-implicit="yes" to="Net::Ping" type="pod">
\&    podpage
\&  </L>
.Ve
.Sp
For example, this Pod source:
.Sp
.Vb 1
\&  L<Net::Ping>
.Ve
.Sp
produces this event structure:
.Sp
.Vb 3
\&  <L content\-implicit="yes" to="Net::Ping" type="pod">
\&    Net::Ping
\&  </L>
.Ve
.Sp
In cases where there is link-text explicitly specified, it
is to be found in the content of the element (and not the
attributes), just as with the L<\fIsometext\fR|\fImanpage(section)\fR>
case discussed above.  For example, this Pod source:
.Sp
.Vb 1
\&  L<Perl Error Messages|perldiag>
.Ve
.Sp
produces this event structure:
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.Vb 3
\&  <L to="perldiag" type="pod">
\&    Perl Error Messages
\&  </L>
.Ve
.Sp
In cases of links to a section in the current Pod document,
there is a \fIsection\fR attribute instead of a \fIto\fR attribute.
For example, this Pod source:
.Sp
.Vb 1
\&  L</"Member Data">
.Ve
.Sp
produces this event structure:
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.Vb 3
\&  <L content\-implicit="yes" section="Member Data" type="pod">
\&    "Member Data"
\&  </L>
.Ve
.Sp
As another example, this Pod source:
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.Vb 1
\&  L<the various attributes|/"Member Data">
.Ve
.Sp
produces this event structure:
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.Vb 3
\&  <L section="Member Data" type="pod">
\&    the various attributes
\&  </L>
.Ve
.Sp
In cases of links to a section in a different Pod document,
there are both a \fIsection\fR attribute and a to attribute.
For example, this Pod source:
.Sp
.Vb 1
\&  L<perlsyn/"Basic BLOCKs and Switch Statements">
.Ve
.Sp
produces this event structure:
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.Vb 3
\&  <L content\-implicit="yes" section="Basic BLOCKs and Switch Statements" to="perlsyn" type="pod">
\&    "Basic BLOCKs and Switch Statements" in perlsyn
\&  </L>
.Ve
.Sp
As another example, this Pod source:
.Sp
.Vb 1
\&  L<SWITCH statements|perlsyn/"Basic BLOCKs and Switch Statements">
.Ve
.Sp
produces this event structure:
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.Vb 3
\&  <L section="Basic BLOCKs and Switch Statements" to="perlsyn" type="pod">
\&    SWITCH statements
\&  </L>
.Ve
.Sp
Incidentally, note that we do not distinguish between these syntaxes:
.Sp
.Vb 4
\&  L</"Member Data">
\&  L<"Member Data">
\&  L</Member Data>
\&  L<Member Data>    [deprecated syntax]
.Ve
.Sp
That is, they all produce the same event structure, namely:
.Sp
.Vb 3
\&  <L content\-implicit="yes" section="Member Data" type="pod">
\&    &#34;Member Data&#34;
\&  </L>
.Ve
.IP "events with an element_name of E or Z" 4
.IX Item "events with an element_name of E or Z"
While there are Pod codes E<...> and Z<>, these
\&\fIdo not\fR produce any E or Z events \*(-- that is, there are no such
events as E or Z.
.IP "events with an element_name of Verbatim" 4
.IX Item "events with an element_name of Verbatim"
When a Pod verbatim paragraph (\s-1AKA\s0 \*(L"codeblock\*(R") is parsed, it
produces this event structure:
.Sp
.Vb 3
\&  <Verbatim start_line="543" xml:space="preserve">
\&    ...text...
\&  </Verbatim>
.Ve
.Sp
The value of the \fIstart_line\fR attribute will be the line number of the
first line of this verbatim block.  The \fIxml:space\fR attribute is always
present, and always has the value \*(L"preserve\*(R".
.Sp
The text content will have tabs already expanded.
.IP "events with an element_name of head1 .. head4" 4
.IX Item "events with an element_name of head1 .. head4"
When a \*(L"=head1 ...\*(R" directive is parsed, it produces this event
structure:
.Sp
.Vb 3
\&  <head1>
\&    ...stuff...
\&  </head1>
.Ve
.Sp
For example, a directive consisting of this:
.Sp
.Vb 1
\&  =head1 Options to C<new> et al.
.Ve
.Sp
will produce this event structure:
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.Vb 7
\&  <head1 start_line="543">
\&    Options to 
\&    <C>
\&      new
\&    </C>
\&     et al.
\&  </head1>
.Ve
.Sp
\&\*(L"=head2\*(R" thru \*(L"=head4\*(R" directives are the same, except for the element
names in the event structure.
.IP "events with an element_name of over-bullet" 4
.IX Item "events with an element_name of over-bullet"
When an \*(L"=over ... =back\*(R" block is parsed where the items are
a bulletted list, it will produce this event structure:
.Sp
.Vb 6
\&  <over\-bullet indent="4" start_line="543">
\&    <item\-bullet start_line="545">
\&      ...Stuff...
\&    </item\-bullet>
\&    ...more item\-bullets...
\&  </over\-bullet>
.Ve
.Sp
The value of the \fIindent\fR attribute is whatever value is after the
\&\*(L"=over\*(R" directive, as in \*(L"=over 8\*(R".  If no such value is specified
in the directive, then the \fIindent\fR attribute has the value \*(L"4\*(R".
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For example, this Pod source:
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.Vb 1
\&  =over
\&
\&  =item *
\&
\&  Stuff
\&
\&  =item *
\&
\&  Bar I<baz>!
\&
\&  =back
.Ve
.Sp
produces this event structure:
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.Vb 8
\&  <over\-bullet indent="4" start_line="10">
\&    <item\-bullet start_line="12">
\&      Stuff
\&    </item\-bullet>
\&    <item\-bullet start_line="14">
\&      Bar <I>baz</I>!
\&    </item\-bullet>
\&  </over\-bullet>
.Ve
.IP "events with an element_name of over-number" 4
.IX Item "events with an element_name of over-number"
When an \*(L"=over ... =back\*(R" block is parsed where the items are
a numbered list, it will produce this event structure:
.Sp
.Vb 6
\&  <over\-number indent="4" start_line="543">
\&    <item\-number number="1" start_line="545">
\&      ...Stuff...
\&    </item\-number>
\&    ...more item\-number...
\&  </over\-bullet>
.Ve
.Sp
This is like the \*(L"over-bullet\*(R" event structure; but note that the contents
are \*(L"item-number\*(R" instead of \*(L"item-bullet\*(R", and note that they will have
a \*(L"number\*(R" attribute, which some formatters/processors may ignore
(since, for example, there's no need for it in \s-1HTML\s0 when producing
an \*(L"<\s-1UL\s0><\s-1LI\s0>...</LI>...</UL>\*(R" structure), but which any processor may use.
.Sp
Note that the values for the \fInumber\fR attributes of \*(L"item-number\*(R"
elements in a given \*(L"over-number\*(R" area \fIwill\fR start at 1 and go up by
one each time.  If the Pod source doesn't follow that order (even though
it really should should!), whatever numbers it has will be ignored (with
the correct values being put in the \fInumber\fR attributes), and an error
message might be issued to the user.
.IP "events with an element_name of over-text" 4
.IX Item "events with an element_name of over-text"
These events are are somewhat unlike the other over\-*
structures, as far as what their contents are.  When
an \*(L"=over ... =back\*(R" block is parsed where the items are
a list of text \*(L"subheadings\*(R", it will produce this event structure:
.Sp
.Vb 8
\&  <over\-text indent="4" start_line="543">
\&    <item\-text>
\&      ...stuff...
\&    </item\-text>
\&    ...stuff (generally Para or Verbatim elements)...
\&    <item\-text>
\&    ...more item\-text and/or stuff...
\&  </over\-text>
.Ve
.Sp
The \fIindent\fR attribute is as with the other over\-* events.
.Sp
For example, this Pod source:
.Sp
.Vb 1
\&  =over
\&  
\&  =item Foo
\&  
\&  Stuff
\&  
\&  =item Bar I<baz>!
\&  
\&  Quux
\&  
\&  =back
.Ve
.Sp
produces this event structure:
.Sp
.Vb 10
\&  <over\-text indent="4" start_line="20">
\&    <item\-text start_line="22">
\&      Foo
\&    </item\-text>
\&    <Para start_line="24">
\&      Stuff
\&    </Para>
\&    <item\-text start_line="26">
\&      Bar
\&        <I>
\&          baz
\&        </I>
\&      !
\&    </item\-text>
\&    <Para start_line="28">
\&      Quux