phpman > perldoc > Pod::Checker(3perl)

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 '=head*N*'

    *   =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.

    *   =head*n* 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 AT enteract.com> (initial version), Marek Rouchal <marekr AT cpan.org>, Marc
    Green <marcgreen AT cpan.org> (port to Pod::Simple) Ricardo Signes <rjbs AT cpan.org> (more porting to
    Pod::Simple) Karl Williamson <khw AT cpan.org> (more porting to Pod::Simple)

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