Provided by: perl-doc_5.26.1-6ubuntu0.7_all bug

NAME

       Pod::Checker - check pod documents for syntax errors

SYNOPSIS

         use Pod::Checker;

         $syntax_okay = podchecker($filepath, $outputpath, %options);

         my $checker = Pod::Checker->new(%options);
         $checker->parse_from_file($filepath, \*STDERR);

OPTIONS/ARGUMENTS

       $filepath is the input POD to read and $outputpath is where to write POD syntax error
       messages. Either argument may be a scalar indicating a file-path, or else a reference to
       an open filehandle.  If unspecified, the input-file it defaults to "\*STDIN", and the
       output-file defaults to "\*STDERR".

   podchecker()
       This function can take a hash of options:

       -warnings => val
           Turn warnings on/off. val is usually 1 for on, but higher values trigger additional
           warnings. See "Warnings".

       -quiet => val
           If "val" is true, do not print any errors/warnings.

DESCRIPTION

       podchecker will perform syntax checking of Perl5 POD format documentation.

       Curious/ambitious users are welcome to propose additional features they wish to see in
       Pod::Checker and podchecker and verify that the checks are consistent with perlpod.

       The following checks are currently performed:

       •   Unknown '=xxxx' commands, unknown 'X<...>' interior-sequences, and unterminated
           interior sequences.

       •   Check for proper balancing of "=begin" and "=end". The contents of such a block are
           generally ignored, i.e. no syntax checks are performed.

       •   Check for proper nesting and balancing of "=over", "=item" and "=back".

       •   Check for same nested interior-sequences (e.g.  "L<...L<...>...>").

       •   Check for malformed or non-existing entities "E<...>".

       •   Check for correct syntax of hyperlinks "L<...>". See perlpod for details.

       •   Check for unresolved document-internal links. This check may also reveal misspelled
           links that seem to be internal links but should be links to something else.

DIAGNOSTICS

   Errors
       •   empty =headn

           A heading ("=head1" or "=head2") without any text? That ain't no heading!

       •   =over on line N without closing =back

       •   You forgot a '=back' before '=headN'

       •   =over is the last thing in the document?!

           The "=over" command does not have a corresponding "=back" before the next heading
           ("=head1" or "=head2") or the end of the file.

       •   '=item' outside of any '=over'

       •   =back without =over

           An "=item" or "=back" command has been found outside a "=over"/"=back" block.

       •   Can't have a 0 in =over N

           You need to indent a strictly positive number of spaces, not 0.

       •   =over should be: '=over' or '=over positive_number'

           Either have an argumentless =over, or have its argument a strictly positive number.

       •   =begin TARGET without matching =end TARGET

           A "=begin" command was found that has no matching =end command.

       •   =begin without a target?

           A "=begin" command was found that is not followed by the formatter specification.

       •   =end TARGET without matching =begin.

           A standalone "=end" command was found.

       •   '=end' without a target?

           '=end' directives need to have a target, just like =begin directives.

       •   '=end TARGET' is invalid.

           TARGET needs to be one word

       •   =end CONTENT doesn't match =begin TARGET

           CONTENT needs to match =begin's TARGET.

       •   =for without a target?

           There is no specification of the formatter after the "=for" command.

       •   unresolved internal link NAME

           The given link to NAME does not have a matching node in the current POD. This also
           happened when a single word node name is not enclosed in "".

       •   Unknown directive: CMD

           An invalid POD command has been found. Valid are "=head1", "=head2", "=head3",
           "=head4", "=over", "=item", "=back", "=begin", "=end", "=for", "=pod", "=cut"

       •   Deleting unknown formatting code SEQ

           An invalid markup command has been encountered. Valid are: "B<>", "C<>", "E<>", "F<>",
           "I<>", "L<>", "S<>", "X<>", "Z<>"

       •   Unterminated SEQ<> sequence

           An unclosed formatting code

       •   An E<...> surrounding strange content

           The STRING found cannot be interpreted as a character entity.

       •   An empty E<>

       •   An empty "L<>"

       •   An empty X<>

           There needs to be content inside E, L, and X formatting codes.

       •   A non-empty Z<>

           The "Z<>" sequence is supposed to be empty.

       •   Spurious text after =pod / =cut

           The commands "=pod" and "=cut" do not take any arguments.

       •   =back doesn't take any parameters, but you said =back ARGUMENT

           The "=back" command does not take any arguments.

       •   =pod directives shouldn't be over one line long!  Ignoring all N lines of content

           Self explanatory

       •   =cut found outside a pod block.

           A '=cut' directive found in the middle of non-POD

       •   Invalid =encoding syntax: CONTENT

           Syntax error in =encoding directive

   Warnings
       These may not necessarily cause trouble, but indicate mediocre style.

       •   nested commands CMD<...CMD<...>...>

           Two nested identical markup commands have been found. Generally this does not make
           sense.

       •   multiple occurrences (N) of link target name

           The POD file has some "=item" and/or "=head" commands that have the same text.
           Potential hyperlinks to such a text cannot be unique then.  This warning is printed
           only with warning level greater than one.

       •   line containing nothing but whitespace in paragraph

           There is some whitespace on a seemingly empty line. POD is very sensitive to such
           things, so this is flagged. vi users switch on the list option to avoid this problem.

       •   =item has no contents

           There is a list "=item" that has no text contents. You probably want to delete empty
           items.

       •   You can't have =items (as at line N) unless the first thing after the =over is an
           =item

           A list introduced by "=over" starts with a text or verbatim paragraph, but continues
           with "=item"s. Move the non-item paragraph out of the "=over"/"=back" block.

       •   Expected '=item EXPECTED VALUE'

       •   Expected '=item *'

       •   Possible =item type mismatch: 'x' found leading a supposed definition =item

           A list started with e.g. a bullet-like "=item" and continued with a numbered one. This
           is obviously inconsistent. For most translators the type of the first "=item"
           determines the type of the list.

       •   You have '=item x' instead of the expected '=item N'

           Erroneous numbering of =item numbers; they need to ascend consecutively.

       •   Unknown E content in E<CONTENT>

           A character entity was found that does not belong to the standard ISO set or the POD
           specials "verbar" and "sol". Currently, this warning only appears if a character
           entity was found that does not have a Unicode character. This should be fixed to
           adhere to the original warning.

       •   empty =over/=back block

           The list opened with "=over" does not contain anything.

       •   empty section in previous paragraph

           The previous section (introduced by a "=head" command) does not contain any valid
           content. This usually indicates that something is missing. Note: A "=head1" followed
           immediately by "=head2" does not trigger this warning.

       •   Verbatim paragraph in NAME section

           The NAME section ("=head1 NAME") should consist of a single paragraph with the
           script/module name, followed by a dash `-' and a very short description of what the
           thing is good for.

       •   =headn without preceding higher level

           For example if there is a "=head2" in the POD file prior to a "=head1".

   Hyperlinks
       There are some warnings with respect to malformed hyperlinks:

       •   ignoring leading/trailing whitespace in link

           There is whitespace at the beginning or the end of the contents of L<...>.

       •   alternative text/node '%s' contains non-escaped | or /

           The characters "|" and "/" are special in the L<...> context.  Although the hyperlink
           parser does its best to determine which "/" is text and which is a delimiter in case
           of doubt, one ought to escape these literal characters like this:

             /     E<sol>
             |     E<verbar>

       Note that the line number of the error/warning may refer to the line number of the start
       of the paragraph in which the error/warning exists, not the line number that the
       error/warning is on. This bug is present in errors/warnings related to formatting codes.
       This should be fixed.

RETURN VALUE

       podchecker returns the number of POD syntax errors found or -1 if there were no POD
       commands at all found in the file.

EXAMPLES

       See "SYNOPSIS"

SCRIPTS

       The podchecker script that comes with this distribution is a lean wrapper around this
       module. See the online manual with

         podchecker -help
         podchecker -man

INTERFACE

       While checking, this module collects document properties, e.g. the nodes for hyperlinks
       ("=headX", "=item") and index entries ("X<>").  POD translators can use this feature to
       syntax-check and get the nodes in a first pass before actually starting to convert. This
       is expensive in terms of execution time, but allows for very robust conversions.

       Since v1.24 the Pod::Checker module uses only the poderror method to print errors and
       warnings. The summary output (e.g.  "Pod syntax OK") has been dropped from the module and
       has been included in podchecker (the script). This allows users of Pod::Checker to control
       completely the output behavior. Users of podchecker (the script) get the well-known
       behavior.

       v1.45 inherits from Pod::Simple as opposed to all previous versions inheriting from
       Pod::Parser. Do not use Pod::Simple's interface when using Pod::Checker unless it is
       documented somewhere on this page. I repeat, DO NOT USE POD::SIMPLE'S INTERFACE.

       "Pod::Checker->new( %options )"
           Return a reference to a new Pod::Checker object that inherits from Pod::Simple and is
           used for calling the required methods later. The following options are recognized:

           "-warnings => num"
             Print warnings if "num" is true. The higher the value of "num", the more warnings
           are printed. Currently there are only levels 1 and 2.

           "-quiet => num"
             If "num" is true, do not print any errors/warnings. This is useful when Pod::Checker
           is used to munge POD code into plain text from within POD formatters.

       "$checker->poderror( @args )"
       "$checker->poderror( {%opts}, @args )"
           Internal method for printing errors and warnings. If no options are given, simply
           prints "@_". The following options are recognized and used to form the output:

             -msg

           A message to print prior to @args.

             -line

           The line number the error occurred in.

             -file

           The file (name) the error occurred in. Defaults to the name of the current file being
           processed.

             -severity

           The error level, should be 'WARNING' or 'ERROR'.

       "$checker->num_errors()"
           Set (if argument specified) and retrieve the number of errors found.

       "$checker->num_warnings()"
           Set (if argument specified) and retrieve the number of warnings found.

       "$checker->name()"
           Set (if argument specified) and retrieve the canonical name of POD as found in the
           "=head1 NAME" section.

       "$checker->node()"
           Add (if argument specified) and retrieve the nodes (as defined by "=headX" and
           "=item") of the current POD. The nodes are returned in the order of their occurrence.
           They consist of plain text, each piece of whitespace is collapsed to a single blank.

       "$checker->idx()"
           Add (if argument specified) and retrieve the index entries (as defined by "X<>") of
           the current POD. They consist of plain text, each piece of whitespace is collapsed to
           a single blank.

       "$checker->hyperlinks()"
           Retrieve an array containing the hyperlinks to things outside the current POD (as
           defined by "L<>").

           Each is an instance of a class with the following methods:

       line()
           Returns the approximate line number in which the link was encountered

       type()
           Returns the type of the link; one of: "url" for things like "http://www.foo", "man"
           for man pages, or "pod".

       page()
           Returns the linked-to page or url.

       node()
           Returns the anchor or node within the linked-to page, or an empty string ("") if none
           appears in the link.

AUTHOR

       Please report bugs using <http://rt.cpan.org>.

       Brad Appleton <bradapp@enteract.com> (initial version), Marek Rouchal <marekr@cpan.org>,
       Marc Green <marcgreen@cpan.org> (port to Pod::Simple) Ricardo Signes <rjbs@cpan.org> (more
       porting to Pod::Simple) Karl Williamson <khw@cpan.org> (more porting to Pod::Simple)

       Based on code for Pod::Text::pod2text() written by Tom Christiansen <tchrist@mox.perl.com>