oracular (3) Pod::Checker.3perl.gz

Provided by: perl-doc_5.38.2-5_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.

       •   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".

       •   A non-empty Z<>

           The "Z<>" sequence is supposed to be empty. Caveat: this issue is detected in Pod::Simple and will be
           flagged as an ERROR by any client code; any contents of "Z<...>" will be disregarded, anyway.

   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.

       The following list documents the overrides to Pod::Simple, primarily to make Pod::Coverage happy:

       end_B
       end_C
       end_Document
       end_F
       end_I
       end_L
       end_Para
       end_S
       end_X
       end_fcode
       end_for
       end_head
       end_head1
       end_head2
       end_head3
       end_head4
       end_item
       end_item_bullet
       end_item_number
       end_item_text
       handle_pod_and_cut
       handle_text
       handle_whiteline
       hyperlink
       scream
       start_B
       start_C
       start_Data
       start_F
       start_I
       start_L
       start_Para
       start_S
       start_Verbatim
       start_X
       start_fcode
       start_for
       start_head
       start_head1
       start_head2
       start_head3
       start_head4
       start_item_bullet
       start_item_number
       start_item_text
       start_over
       start_over_block
       start_over_bullet
       start_over_empty
       start_over_number
       start_over_text
       whine
       "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>