require 5; package Pod::Simple::PullParser; $VERSION = '3.43'; use Pod::Simple (); BEGIN {@ISA = ('Pod::Simple')} use strict; use Carp (); use Pod::Simple::PullParserStartToken; use Pod::Simple::PullParserEndToken; use Pod::Simple::PullParserTextToken; BEGIN { *DEBUG = \&Pod::Simple::DEBUG unless defined &DEBUG } __PACKAGE__->_accessorize( 'source_fh', # the filehandle we're reading from 'source_scalar_ref', # the scalarref we're reading from 'source_arrayref', # the arrayref we're reading from ); #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ # # And here is how we implement a pull-parser on top of a push-parser... sub filter { my($self, $source) = @_; $self = $self->new unless ref $self; $source = *STDIN{IO} unless defined $source; $self->set_source($source); $self->output_fh(*STDOUT{IO}); $self->run; # define run() in a subclass if you want to use filter()! return $self; } # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - sub parse_string_document { my $this = shift; $this->set_source(\ $_[0]); $this->run; } sub parse_file { my($this, $filename) = @_; $this->set_source($filename); $this->run; } # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - # In case anyone tries to use them: sub run { use Carp (); if( __PACKAGE__ eq ref($_[0]) || $_[0]) { # I'm not being subclassed! Carp::croak "You can call run() only on subclasses of " . __PACKAGE__; } else { Carp::croak join '', "You can't call run() because ", ref($_[0]) || $_[0], " didn't define a run() method"; } } sub parse_lines { use Carp (); Carp::croak "Use set_source with ", __PACKAGE__, " and subclasses, not parse_lines"; } sub parse_line { use Carp (); Carp::croak "Use set_source with ", __PACKAGE__, " and subclasses, not parse_line"; } #~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sub new { my $class = shift; my $self = $class->SUPER::new(@_); die "Couldn't construct for $class" unless $self; $self->{'token_buffer'} ||= []; $self->{'start_token_class'} ||= 'Pod::Simple::PullParserStartToken'; $self->{'text_token_class'} ||= 'Pod::Simple::PullParserTextToken'; $self->{'end_token_class'} ||= 'Pod::Simple::PullParserEndToken'; DEBUG > 1 and print STDERR "New pullparser object: $self\n"; return $self; } # ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ sub get_token { my $self = shift; DEBUG > 1 and print STDERR "\nget_token starting up on $self.\n"; DEBUG > 2 and print STDERR " Items in token-buffer (", scalar( @{ $self->{'token_buffer'} } ) , ") :\n", map( " " . $_->dump . "\n", @{ $self->{'token_buffer'} } ), @{ $self->{'token_buffer'} } ? '' : ' (no tokens)', "\n" ; until( @{ $self->{'token_buffer'} } ) { DEBUG > 3 and print STDERR "I need to get something into my empty token buffer...\n"; if($self->{'source_dead'}) { DEBUG and print STDERR "$self 's source is dead.\n"; push @{ $self->{'token_buffer'} }, undef; } elsif(exists $self->{'source_fh'}) { my @lines; my $fh = $self->{'source_fh'} || Carp::croak('You have to call set_source before you can call get_token'); DEBUG and print STDERR "$self 's source is filehandle $fh.\n"; # Read those many lines at a time for(my $i = Pod::Simple::MANY_LINES; $i--;) { DEBUG > 3 and print STDERR " Fetching a line from source filehandle $fh...\n"; local $/ = $Pod::Simple::NL; push @lines, scalar(<$fh>); # readline DEBUG > 3 and print STDERR " Line is: ", defined($lines[-1]) ? $lines[-1] : "\n"; unless( defined $lines[-1] ) { DEBUG and print STDERR "That's it for that source fh! Killing.\n"; delete $self->{'source_fh'}; # so it can be GC'd last; } # but pass thru the undef, which will set source_dead to true # TODO: look to see if $lines[-1] is =encoding, and if so, # do horribly magic things } if(DEBUG > 8) { print STDERR "* I've gotten ", scalar(@lines), " lines:\n"; foreach my $l (@lines) { if(defined $l) { print STDERR " line {$l}\n"; } else { print STDERR " line undef\n"; } } print STDERR "* end of ", scalar(@lines), " lines\n"; } $self->SUPER::parse_lines(@lines); } elsif(exists $self->{'source_arrayref'}) { DEBUG and print STDERR "$self 's source is arrayref $self->{'source_arrayref'}, with ", scalar(@{$self->{'source_arrayref'}}), " items left in it.\n"; DEBUG > 3 and print STDERR " Fetching ", Pod::Simple::MANY_LINES, " lines.\n"; $self->SUPER::parse_lines( splice @{ $self->{'source_arrayref'} }, 0, Pod::Simple::MANY_LINES ); unless( @{ $self->{'source_arrayref'} } ) { DEBUG and print STDERR "That's it for that source arrayref! Killing.\n"; $self->SUPER::parse_lines(undef); delete $self->{'source_arrayref'}; # so it can be GC'd } # to make sure that an undef is always sent to signal end-of-stream } elsif(exists $self->{'source_scalar_ref'}) { DEBUG and print STDERR "$self 's source is scalarref $self->{'source_scalar_ref'}, with ", length(${ $self->{'source_scalar_ref'} }) - (pos(${ $self->{'source_scalar_ref'} }) || 0), " characters left to parse.\n"; DEBUG > 3 and print STDERR " Fetching a line from source-string...\n"; if( ${ $self->{'source_scalar_ref'} } =~ m/([^\n\r]*)((?:\r?\n)?)/g ) { #print(">> $1\n"), $self->SUPER::parse_lines($1) if length($1) or length($2) or pos( ${ $self->{'source_scalar_ref'} }) != length( ${ $self->{'source_scalar_ref'} }); # I.e., unless it's a zero-length "empty line" at the very # end of "foo\nbar\n" (i.e., between the \n and the EOS). } else { # that's the end. Byebye $self->SUPER::parse_lines(undef); delete $self->{'source_scalar_ref'}; DEBUG and print STDERR "That's it for that source scalarref! Killing.\n"; } } else { die "What source??"; } } DEBUG and print STDERR "get_token about to return ", Pod::Simple::pretty( @{$self->{'token_buffer'}} ? $self->{'token_buffer'}[-1] : undef ), "\n"; return shift @{$self->{'token_buffer'}}; # that's an undef if empty } sub unget_token { my $self = shift; DEBUG and print STDERR "Ungetting ", scalar(@_), " tokens: ", @_ ? "@_\n" : "().\n"; foreach my $t (@_) { Carp::croak "Can't unget that, because it's not a token -- it's undef!" unless defined $t; Carp::croak "Can't unget $t, because it's not a token -- it's a string!" unless ref $t; Carp::croak "Can't unget $t, because it's not a token object!" unless UNIVERSAL::can($t, 'type'); } unshift @{$self->{'token_buffer'}}, @_; DEBUG > 1 and print STDERR "Token buffer now has ", scalar(@{$self->{'token_buffer'}}), " items in it.\n"; return; } #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ # $self->{'source_filename'} = $source; sub set_source { my $self = shift @_; return $self->{'source_fh'} unless @_; Carp::croak("Cannot assign new source to pull parser; create a new instance, instead") if $self->{'source_fh'} || $self->{'source_scalar_ref'} || $self->{'source_arrayref'}; my $handle; if(!defined $_[0]) { Carp::croak("Can't use empty-string as a source for set_source"); } elsif(ref(\( $_[0] )) eq 'GLOB') { $self->{'source_filename'} = '' . ($handle = $_[0]); DEBUG and print STDERR "$self 's source is glob $_[0]\n"; # and fall thru } elsif(ref( $_[0] ) eq 'SCALAR') { $self->{'source_scalar_ref'} = $_[0]; DEBUG and print STDERR "$self 's source is scalar ref $_[0]\n"; return; } elsif(ref( $_[0] ) eq 'ARRAY') { $self->{'source_arrayref'} = $_[0]; DEBUG and print STDERR "$self 's source is array ref $_[0]\n"; return; } elsif(ref $_[0]) { $self->{'source_filename'} = '' . ($handle = $_[0]); DEBUG and print STDERR "$self 's source is fh-obj $_[0]\n"; } elsif(!length $_[0]) { Carp::croak("Can't use empty-string as a source for set_source"); } else { # It's a filename! DEBUG and print STDERR "$self 's source is filename $_[0]\n"; { local *PODSOURCE; open(PODSOURCE, "<$_[0]") || Carp::croak "Can't open $_[0]: $!"; $handle = *PODSOURCE{IO}; } $self->{'source_filename'} = $_[0]; DEBUG and print STDERR " Its name is $_[0].\n"; # TODO: file-discipline things here! } $self->{'source_fh'} = $handle; DEBUG and print STDERR " Its handle is $handle\n"; return 1; } # ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ sub get_title_short { shift->get_short_title(@_) } # alias sub get_short_title { my $title = shift->get_title(@_); $title = $1 if $title =~ m/^(\S{1,60})\s+--?\s+./s; # turn "Foo::Bar -- bars for your foo" into "Foo::Bar" return $title; } sub get_title { shift->_get_titled_section( 'NAME', max_token => 50, desperate => 1, @_) } sub get_version { shift->_get_titled_section( 'VERSION', max_token => 400, accept_verbatim => 1, max_content_length => 3_000, @_, ); } sub get_description { shift->_get_titled_section( 'DESCRIPTION', max_token => 400, max_content_length => 3_000, @_, ) } sub get_authors { shift->get_author(@_) } # a harmless alias sub get_author { my $this = shift; # Max_token is so high because these are # typically at the end of the document: $this->_get_titled_section('AUTHOR' , max_token => 10_000, @_) || $this->_get_titled_section('AUTHORS', max_token => 10_000, @_); } #-------------------------------------------------------------------------- sub _get_titled_section { # Based on a get_title originally contributed by Graham Barr my($self, $titlename, %options) = (@_); my $max_token = delete $options{'max_token'}; my $desperate_for_title = delete $options{'desperate'}; my $accept_verbatim = delete $options{'accept_verbatim'}; my $max_content_length = delete $options{'max_content_length'}; my $nocase = delete $options{'nocase'}; $max_content_length = 120 unless defined $max_content_length; Carp::croak( "Unknown " . ((1 == keys %options) ? "option: " : "options: ") . join " ", map "[$_]", sort keys %options ) if keys %options; my %content_containers; $content_containers{'Para'} = 1; if($accept_verbatim) { $content_containers{'Verbatim'} = 1; $content_containers{'VerbatimFormatted'} = 1; } my $token_count = 0; my $title; my @to_unget; my $state = 0; my $depth = 0; Carp::croak "What kind of titlename is \"$titlename\"?!" unless defined $titlename and $titlename =~ m/^[A-Z ]{1,60}$/s; #sanity my $titlename_re = quotemeta($titlename); my $head1_text_content; my $para_text_content; my $skipX; while( ++$token_count <= ($max_token || 1_000_000) and defined(my $token = $self->get_token) ) { push @to_unget, $token; if ($state == 0) { # seeking =head1 if( $token->is_start and $token->tagname eq 'head1' ) { DEBUG and print STDERR " Found head1. Seeking content...\n"; ++$state; $head1_text_content = ''; } } elsif($state == 1) { # accumulating text until end of head1 if( $token->is_text ) { unless ($skipX) { DEBUG and print STDERR " Adding \"", $token->text, "\" to head1-content.\n"; $head1_text_content .= $token->text; } } elsif( $token->is_tagname('X') ) { # We're going to want to ignore X<> stuff. $skipX = $token->is_start; DEBUG and print STDERR +($skipX ? 'Start' : 'End'), 'ing ignoring of X<> tag'; } elsif( $token->is_end and $token->tagname eq 'head1' ) { DEBUG and print STDERR " Found end of head1. Considering content...\n"; $head1_text_content = uc $head1_text_content if $nocase; if($head1_text_content eq $titlename or $head1_text_content =~ m/\($titlename_re\)/s # We accept "=head1 Nomen Modularis (NAME)" for sake of i18n ) { DEBUG and print STDERR " Yup, it was $titlename. Seeking next para-content...\n"; ++$state; } elsif( $desperate_for_title # if we're so desperate we'll take the first # =head1's content as a title and $head1_text_content =~ m/\S/ and $head1_text_content !~ m/^[ A-Z]+$/s and $head1_text_content !~ m/\((?: NAME | TITLE | VERSION | AUTHORS? | DESCRIPTION | SYNOPSIS | COPYRIGHT | LICENSE | NOTES? | FUNCTIONS? | METHODS? | CAVEATS? | BUGS? | SEE\ ALSO | SWITCHES | ENVIRONMENT )\)/sx # avoid accepting things like =head1 Thingy Thongy (DESCRIPTION) and ($max_content_length ? (length($head1_text_content) <= $max_content_length) # sanity : 1) ) { # Looks good; trim it ($title = $head1_text_content) =~ s/\s+$//; DEBUG and print STDERR " It looks titular: \"$title\".\n\n Using that.\n"; last; } else { --$state; DEBUG and print STDERR " Didn't look titular ($head1_text_content).\n", "\n Dropping back to seeking-head1-content mode...\n"; } } } elsif($state == 2) { # seeking start of para (which must immediately follow) if($token->is_start and $content_containers{ $token->tagname }) { DEBUG and print STDERR " Found start of Para. Accumulating content...\n"; $para_text_content = ''; ++$state; } else { DEBUG and print " Didn't see an immediately subsequent start-Para. Reseeking H1\n"; $state = 0; } } elsif($state == 3) { # accumulating text until end of Para if( $token->is_text ) { DEBUG and print STDERR " Adding \"", $token->text, "\" to para-content.\n"; $para_text_content .= $token->text; # and keep looking } elsif( $token->is_end and $content_containers{ $token->tagname } ) { DEBUG and print STDERR " Found end of Para. Considering content: ", $para_text_content, "\n"; if( $para_text_content =~ m/\S/ and ($max_content_length ? (length($para_text_content) <= $max_content_length) : 1) ) { # Some minimal sanity constraints, I think. DEBUG and print STDERR " It looks contentworthy, I guess. Using it.\n"; $title = $para_text_content; last; } else { DEBUG and print STDERR " Doesn't look at all contentworthy!\n Giving up.\n"; undef $title; last; } } } else { die "IMPOSSIBLE STATE $state!\n"; # should never happen } } # Put it all back! $self->unget_token(@to_unget); if(DEBUG) { if(defined $title) { print STDERR " Returning title <$title>\n" } else { print STDERR "Returning title <>\n" } } return '' unless defined $title; $title =~ s/^\s+//; return $title; } #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ # # Methods that actually do work at parse-time: sub _handle_element_start { my $self = shift; # leaving ($element_name, $attr_hash_r) DEBUG > 2 and print STDERR "++ $_[0] (", map("<$_> ", %{$_[1]}), ")\n"; push @{ $self->{'token_buffer'} }, $self->{'start_token_class'}->new(@_); return; } sub _handle_text { my $self = shift; # leaving ($text) DEBUG > 2 and print STDERR "== $_[0]\n"; push @{ $self->{'token_buffer'} }, $self->{'text_token_class'}->new(@_); return; } sub _handle_element_end { my $self = shift; # leaving ($element_name); DEBUG > 2 and print STDERR "-- $_[0]\n"; push @{ $self->{'token_buffer'} }, $self->{'end_token_class'}->new(@_); return; } #@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1; __END__ =head1 NAME Pod::Simple::PullParser -- a pull-parser interface to parsing Pod =head1 SYNOPSIS my $parser = SomePodProcessor->new; $parser->set_source( "whatever.pod" ); $parser->run; Or: my $parser = SomePodProcessor->new; $parser->set_source( $some_filehandle_object ); $parser->run; Or: my $parser = SomePodProcessor->new; $parser->set_source( \$document_source ); $parser->run; Or: my $parser = SomePodProcessor->new; $parser->set_source( \@document_lines ); $parser->run; And elsewhere: require 5; package SomePodProcessor; use strict; use base qw(Pod::Simple::PullParser); sub run { my $self = shift; Token: while(my $token = $self->get_token) { ...process each token... } } =head1 DESCRIPTION This class is for using Pod::Simple to build a Pod processor -- but one that uses an interface based on a stream of token objects, instead of based on events. This is a subclass of L and inherits all its methods. A subclass of Pod::Simple::PullParser should define a C method that calls C<< $token = $parser->get_token >> to pull tokens. See the source for Pod::Simple::RTF for an example of a formatter that uses Pod::Simple::PullParser. =head1 METHODS =over =item my $token = $parser->get_token This returns the next token object (which will be of a subclass of L), or undef if the parser-stream has hit the end of the document. =item $parser->unget_token( $token ) =item $parser->unget_token( $token1, $token2, ... ) This restores the token object(s) to the front of the parser stream. =back The source has to be set before you can parse anything. The lowest-level way is to call C: =over =item $parser->set_source( $filename ) =item $parser->set_source( $filehandle_object ) =item $parser->set_source( \$document_source ) =item $parser->set_source( \@document_lines ) =back Or you can call these methods, which Pod::Simple::PullParser has defined to work just like Pod::Simple's same-named methods: =over =item $parser->parse_file(...) =item $parser->parse_string_document(...) =item $parser->filter(...) =item $parser->parse_from_file(...) =back For those to work, the Pod-processing subclass of Pod::Simple::PullParser has to have defined a $parser->run method -- so it is advised that all Pod::Simple::PullParser subclasses do so. See the Synopsis above, or the source for Pod::Simple::RTF. Authors of formatter subclasses might find these methods useful to call on a parser object that you haven't started pulling tokens from yet: =over =item my $title_string = $parser->get_title This tries to get the title string out of $parser, by getting some tokens, and scanning them for the title, and then ungetting them so that you can process the token-stream from the beginning. For example, suppose you have a document that starts out: =head1 NAME Hoo::Boy::Wowza -- Stuff B yeah! $parser->get_title on that document will return "Hoo::Boy::Wowza -- Stuff wow yeah!". If the document starts with: =head1 Name Hoo::Boy::W00t -- Stuff B yeah! Then you'll need to pass the C option in order to recognize "Name": $parser->get_title(nocase => 1); In cases where get_title can't find the title, it will return empty-string (""). =item my $title_string = $parser->get_short_title This is just like get_title, except that it returns just the modulename, if the title seems to be of the form "SomeModuleName -- description". For example, suppose you have a document that starts out: =head1 NAME Hoo::Boy::Wowza -- Stuff B yeah! then $parser->get_short_title on that document will return "Hoo::Boy::Wowza". But if the document starts out: =head1 NAME Hooboy, stuff B yeah! then $parser->get_short_title on that document will return "Hooboy, stuff wow yeah!". If the document starts with: =head1 Name Hoo::Boy::W00t -- Stuff B yeah! Then you'll need to pass the C option in order to recognize "Name": $parser->get_short_title(nocase => 1); If the title can't be found, then get_short_title returns empty-string (""). =item $author_name = $parser->get_author This works like get_title except that it returns the contents of the "=head1 AUTHOR\n\nParagraph...\n" section, assuming that that section isn't terribly long. To recognize a "=head1 Author\n\nParagraph\n" section, pass the C option: $parser->get_author(nocase => 1); (This method tolerates "AUTHORS" instead of "AUTHOR" too.) =item $description_name = $parser->get_description This works like get_title except that it returns the contents of the "=head1 DESCRIPTION\n\nParagraph...\n" section, assuming that that section isn't terribly long. To recognize a "=head1 Description\n\nParagraph\n" section, pass the C option: $parser->get_description(nocase => 1); =item $version_block = $parser->get_version This works like get_title except that it returns the contents of the "=head1 VERSION\n\n[BIG BLOCK]\n" block. Note that this does NOT return the module's C<$VERSION>!! To recognize a "=head1 Version\n\n[BIG BLOCK]\n" section, pass the C option: $parser->get_version(nocase => 1); =back =head1 NOTE You don't actually I to define a C method. If you're writing a Pod-formatter class, you should define a C just so that users can call C etc, but you don't I to. And if you're not writing a formatter class, but are instead just writing a program that does something simple with a Pod::PullParser object (and not an object of a subclass), then there's no reason to bother subclassing to add a C method. =head1 SEE ALSO L L -- and its subclasses L, L, and L. L, which inspired this. =head1 SUPPORT 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, L. Feel free to fork and contribute, or to clone L and send patches! Patches against Pod::Simple are welcome. Please send bug reports to . =head1 COPYRIGHT AND DISCLAIMERS 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. =head1 AUTHOR Pod::Simple was created by Sean M. Burke . But don't bother him, he's retired. Pod::Simple is maintained by: =over =item * Allison Randal C =item * Hans Dieter Pearcey C =item * David E. Wheeler C =back =cut JUNK: sub _old_get_title { # some witchery in here my $self = $_[0]; my $title; my @to_unget; while(1) { push @to_unget, $self->get_token; unless(defined $to_unget[-1]) { # whoops, short doc! pop @to_unget; last; } DEBUG and print STDERR "-Got token ", $to_unget[-1]->dump, "\n"; (DEBUG and print STDERR "Too much in the buffer.\n"), last if @to_unget > 25; # sanity my $pattern = ''; if( #$to_unget[-1]->type eq 'end' #and $to_unget[-1]->tagname eq 'Para' #and ($pattern = join('', map {; ($_->type eq 'start') ? ("<" . $_->tagname .">") : ($_->type eq 'end' ) ? ("tagname .">") : ($_->type eq 'text' ) ? ($_->text =~ m<^([A-Z]+)$>s ? $1 : 'X') : "BLORP" } @to_unget )) =~ m{NAME(X|)+$}s ) { # Whee, it fits the pattern DEBUG and print STDERR "Seems to match =head1 NAME pattern.\n"; $title = ''; foreach my $t (reverse @to_unget) { last if $t->type eq 'start' and $t->tagname eq 'Para'; $title = $t->text . $title if $t->type eq 'text'; } undef $title if $title =~ m<^\s*$>; # make sure it's contentful! last; } elsif ($pattern =~ m{(.+)$} and !( $1 eq '1' and $2 eq 'NAME' ) ) { # Well, it fits a fallback pattern DEBUG and print STDERR "Seems to match NAMEless pattern.\n"; $title = ''; foreach my $t (reverse @to_unget) { last if $t->type eq 'start' and $t->tagname =~ m/^head\d$/s; $title = $t->text . $title if $t->type eq 'text'; } undef $title if $title =~ m<^\s*$>; # make sure it's contentful! last; } else { DEBUG and $pattern and print STDERR "Leading pattern: $pattern\n"; } } # Put it all back: $self->unget_token(@to_unget); if(DEBUG) { if(defined $title) { print STDERR " Returning title <$title>\n" } else { print STDERR "Returning title <>\n" } } return '' unless defined $title; return $title; }