- TODO
Pod::Simple is a Perl library for parsing text in the Pod ("plain old
documentation") markup language that is typically used for writing
documentation for Perl and for Perl modules. The Pod format is explained
in perlpod; the most common formatter is called perldoc
.
Be sure to read ENCODING if your Pod contains non-ASCII characters.
Pod formatters can use Pod::Simple to parse Pod documents and render them into
plain text, HTML, or any number of other formats. Typically, such formatters
will be subclasses of Pod::Simple, and so they will inherit its methods, like
parse_file
.
If you're reading this document just because you have a Pod-processing subclass that you want to use, this document (plus the documentation for the subclass) is probably all you need to read.
If you're reading this document because you want to write a formatter subclass, continue reading it and then read Pod::Simple::Subclassing, and then possibly even read perlpodspec (some of which is for parser-writers, but much of which is notes to formatter-writers).
$parser = SomeClass->new();
This returns a new parser object, where SomeClass
is a subclass
of Pod::Simple.
$parser->output_fh( *OUT );
This sets the filehandle that $parser
's output will be written to.
You can pass *STDOUT
or *STDERR
, otherwise you should probably do
something like this:
...before you call one of the $parser->parse_whatever methods.
$parser->output_string( \$somestring );
This sets the string that $parser
's output will be sent to,
instead of any filehandle.
$parser->parse_file( $some_filename );
$parser->parse_file( *INPUT_FH );
This reads the Pod content of the file (or filehandle) that you specify,
and processes it with that $parser
object, according to however
$parser
's class works, and according to whatever parser options you
have set up for this $parser
object.
$parser->parse_string_document( $all_content );
This works just like parse_file
except that it reads the Pod
content not from a file, but from a string that you have already
in memory.
$parser->parse_lines( ...@lines..., undef );
This processes the lines in @lines
(where each list item must be a
defined value, and must contain exactly one line of content -- so no
items like "foo\nbar"
are allowed). The final undef is used to
indicate the end of document being parsed.
The other parser_whatever methods are meant to be called only once
per $parser
object; but parse_lines
can be called as many times per
$parser
object as you want, as long as the last call (and only
the last call) ends with an undef value.
$parser->content_seen
This returns true only if there has been any real content seen for this document. Returns false in cases where the document contains content, but does not make use of any Pod markup.
SomeClass->filter( $filename );
SomeClass->filter( *INPUT_FH );
SomeClass->filter( \$document_content );
This is a shortcut method for creating a new parser object, setting the output handle to STDOUT, and then processing the specified file (or filehandle, or in-memory document). This is handy for one-liners like this:
- perl -MPod::Simple::Text -e "Pod::Simple::Text->filter('thingy.pod')"
Some of these methods might be of interest to general users, as well as of interest to formatter-writers.
Note that the general pattern here is that the accessor-methods
read the attribute's value with $value = $parser->attribute
and set the attribute's value with
$parser->attribute(newvalue). For each accessor, I typically
only mention one syntax or another, based on which I think you are actually
most likely to use.
$parser->parse_characters( SOMEVALUE )
The Pod parser normally expects to read octets and to convert those octets
to characters based on the =encoding
declaration in the Pod source. Set
this option to a true value to indicate that the Pod source is already a Perl
character stream. This tells the parser to ignore any =encoding
command
and to skip all the code paths involving decoding octets.
$parser->no_whining( SOMEVALUE )
If you set this attribute to a true value, you will suppress the parser's complaints about irregularities in the Pod coding. By default, this attribute's value is false, meaning that irregularities will be reported.
Note that turning this attribute to true won't suppress one or two kinds of complaints about rarely occurring unrecoverable errors.
$parser->no_errata_section( SOMEVALUE )
If you set this attribute to a true value, you will stop the parser from generating a "POD ERRORS" section at the end of the document. By default, this attribute's value is false, meaning that an errata section will be generated, as necessary.
$parser->complain_stderr( SOMEVALUE )
If you set this attribute to a true value, it will send reports of parsing errors to STDERR. By default, this attribute's value is false, meaning that no output is sent to STDERR.
Setting complain_stderr
also sets no_errata_section
.
$parser->source_filename
This returns the filename that this parser object was set to read from.
$parser->doc_has_started
This returns true if $parser
has read from a source, and has seen
Pod content in it.
$parser->source_dead
This returns true if $parser
has read from a source, and come to the
end of that source.
$parser->strip_verbatim_indent( SOMEVALUE )
The perlpod spec for a Verbatim paragraph is "It should be reproduced exactly...", which means that the whitespace you've used to indent your verbatim blocks will be preserved in the output. This can be annoying for outputs such as HTML, where that whitespace will remain in front of every line. It's an unfortunate case where syntax is turned into semantics.
If the POD you're parsing adheres to a consistent indentation policy, you can have such indentation stripped from the beginning of every line of your verbatim blocks. This method tells Pod::Simple what to strip. For two-space indents, you'd use:
- $parser->strip_verbatim_indent(' ');
For tab indents, you'd use a tab character:
- $parser->strip_verbatim_indent("\t");
If the POD is inconsistent about the indentation of verbatim blocks, but you have figured out a heuristic to determine how much a particular verbatim block is indented, you can pass a code reference instead. The code reference will be executed with one argument, an array reference of all the lines in the verbatim block, and should return the value to be stripped from each line. For example, if you decide that you're fine to use the first line of the verbatim block to set the standard for indentation of the rest of the block, you can look at the first line and return the appropriate value, like so:
If you'd rather treat each line individually, you can do that, too, by just
transforming them in-place in the code reference and returning undef. Say
that you don't want any lines indented. You can do something like this:
- $new->strip_verbatim_indent(sub {
- my $lines = shift;
- sub { s/^\s+// for @{ $lines },
- return undef;
- });
$parser->abandon_output_fh()
Cancel output to the file handle. Any POD read by the $parser
is not
effected.
$parser->abandon_output_string()
Cancel output to the output string. Any POD read by the $parser
is not
effected.
$parser->accept_code( @codes )
Alias for accept_codes.
$parser->accept_codes( @codes )
Allows $parser
to accept a list of Formatting Codes in perlpod. This can be
used to implement user-defined codes.
$parser->accept_directive_as_data( @directives )
Allows $parser
to accept a list of directives for data paragraphs. A
directive is the label of a Command Paragraph in perlpod. A data paragraph is
one delimited by =begin/=for/=end
directives. This can be used to
implement user-defined directives.
$parser->accept_directive_as_processed( @directives )
Allows $parser
to accept a list of directives for processed paragraphs. A
directive is the label of a Command Paragraph in perlpod. A processed
paragraph is also known as Ordinary Paragraph in perlpod. This can be used to
implement user-defined directives.
$parser->accept_directive_as_verbatim( @directives )
Allows $parser
to accept a list of directives for Verbatim Paragraph in perlpod. A directive is the label of a Command Paragraph in perlpod. This
can be used to implement user-defined directives.
$parser->accept_target( @targets )
Alias for accept_targets.
$parser->accept_target_as_text( @targets )
Alias for accept_targets_as_text.
$parser->accept_targets( @targets )
Accepts targets for =begin/=for/=end
sections of the POD.
$parser->accept_targets_as_text( @targets )
Accepts targets for =begin/=for/=end
sections that should be parsed as
POD. For details, see About Data Paragraphs in perlpodspec.
$parser->any_errata_seen()
Used to check if any errata was seen.
Example:
$parser->errata_seen()
Returns a hash reference of all errata seen, both whines and screams. The hash reference's keys are the line number and the value is an array reference of the errors for that line.
Example:
- if ( $parser->any_errata_seen() ) {
- $logger->log( $parser->errata_seen() );
- }
$parser->detected_encoding()
Return the encoding corresponding to =encoding
, but only if the
encoding was recognized and handled.
$parser->encoding()
Return encoding of the document, even if the encoding is not correctly handled.
$parser->parse_from_file( $source, $to )
Parses from $source
file to $to
file. Similar to parse_from_file in Pod::Parser.
$parser->scream( @error_messages )
Log an error that can't be ignored.
$parser->unaccept_code( @codes )
Alias for unaccept_codes.
$parser->unaccept_codes( @codes )
Removes @codes
as valid codes for the parse.
$parser->unaccept_directive( @directives )
Alias for unaccept_directives.
$parser->unaccept_directives( @directives )
Removes @directives
as valid directives for the parse.
$parser->unaccept_target( @targets )
Alias for unaccept_targets.
$parser->unaccept_targets( @targets )
Removes @targets
as valid targets for the parse.
$parser->version_report()
Returns a string describing the version.
$parser->whine( @error_messages )
Log an error unless $parser->no_whining( TRUE );
.
The Pod::Simple parser expects to read octets. The parser will decode the
octets into Perl's internal character string representation using the value of
the =encoding
declaration in the POD source.
If the POD source does not include an =encoding
declaration, the parser will
attempt to guess the encoding (selecting one of UTF-8 or CP 1252) by examining
the first non-ASCII bytes and applying the heuristic described in
perlpodspec. (If the POD source contains only ASCII bytes, the
encoding is assumed to be ASCII.)
If you set the parse_characters
option to a true value the parser will
expect characters rather than octets; will ignore any =encoding
; and will
make no attempt to decode the input.
Questions or discussion about POD and Pod::Simple should be sent to the pod-people@perl.org mail list. Send an empty email to pod-people-subscribe@perl.org to subscribe.
This module is managed in an open GitHub repository, https://github.com/perl-pod/pod-simple/. Feel free to fork and contribute, or to clone git://github.com/perl-pod/pod-simple.git and send patches!
Patches against Pod::Simple are welcome. Please send bug reports to <bug-pod-simple@rt.cpan.org>.
Copyright (c) 2002 Sean M. Burke.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose.
Pod::Simple was created by Sean M. Burke <sburke@cpan.org>. But don't bother him, he's retired.
Pod::Simple is maintained by:
Documentation has been contributed by: