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diff --git a/lib/Pod/InputObjects.pm b/lib/Pod/InputObjects.pm new file mode 100644 index 0000000000..9bbc6cf7ac --- /dev/null +++ b/lib/Pod/InputObjects.pm @@ -0,0 +1,903 @@ +############################################################################# +# Pod/InputObjects.pm -- package which defines objects for input streams +# and paragraphs and commands when parsing POD docs. +# +# Copyright (C) 1996-1999 Tom Christiansen. All rights reserved. +# This file is part of "PodParser". PodParser is free software; +# you can redistribute it and/or modify it under the same terms +# as Perl itself. +############################################################################# + +package Pod::InputObjects; + +use vars qw($VERSION); +$VERSION = 1.08; ## Current version of this package +require 5.004; ## requires this Perl version or later + +############################################################################# + +=head1 NAME + +Pod::InputObjects - objects representing POD input paragraphs, commands, etc. + +=head1 SYNOPSIS + + use Pod::InputObjects; + +=head1 REQUIRES + +perl5.004, Carp + +=head1 EXPORTS + +Nothing. + +=head1 DESCRIPTION + +This module defines some basic input objects used by B<Pod::Parser> when +reading and parsing POD text from an input source. The following objects +are defined: + +=over 4 + +=begin __PRIVATE__ + +=item B<Pod::InputSource> + +An object corresponding to a source of POD input text. It is mostly a +wrapper around a filehandle or C<IO::Handle>-type object (or anything +that implements the C<getline()> method) which keeps track of some +additional information relevant to the parsing of PODs. + +=end __PRIVATE__ + +=item B<Pod::Paragraph> + +An object corresponding to a paragraph of POD input text. It may be a +plain paragraph, a verbatim paragraph, or a command paragraph (see +L<perlpod>). + +=item B<Pod::InteriorSequence> + +An object corresponding to an interior sequence command from the POD +input text (see L<perlpod>). + +=item B<Pod::ParseTree> + +An object corresponding to a tree of parsed POD text. Each "node" in +a parse-tree (or I<ptree>) is either a text-string or a reference to +a B<Pod::InteriorSequence> object. The nodes appear in the parse-tree +in they order in which they were parsed from left-to-right. + +=back + +Each of these input objects are described in further detail in the +sections which follow. + +=cut + +############################################################################# + +use strict; +#use diagnostics; +#use Carp; + +############################################################################# + +package Pod::InputSource; + +##--------------------------------------------------------------------------- + +=begin __PRIVATE__ + +=head1 B<Pod::InputSource> + +This object corresponds to an input source or stream of POD +documentation. When parsing PODs, it is necessary to associate and store +certain context information with each input source. All of this +information is kept together with the stream itself in one of these +C<Pod::InputSource> objects. Each such object is merely a wrapper around +an C<IO::Handle> object of some kind (or at least something that +implements the C<getline()> method). They have the following +methods/attributes: + +=end __PRIVATE__ + +=cut + +##--------------------------------------------------------------------------- + +=begin __PRIVATE__ + +=head2 B<new()> + + my $pod_input1 = Pod::InputSource->new(-handle => $filehandle); + my $pod_input2 = new Pod::InputSource(-handle => $filehandle, + -name => $name); + my $pod_input3 = new Pod::InputSource(-handle => \*STDIN); + my $pod_input4 = Pod::InputSource->new(-handle => \*STDIN, + -name => "(STDIN)"); + +This is a class method that constructs a C<Pod::InputSource> object and +returns a reference to the new input source object. It takes one or more +keyword arguments in the form of a hash. The keyword C<-handle> is +required and designates the corresponding input handle. The keyword +C<-name> is optional and specifies the name associated with the input +handle (typically a file name). + +=end __PRIVATE__ + +=cut + +sub new { + ## Determine if we were called via an object-ref or a classname + my $this = shift; + my $class = ref($this) || $this; + + ## Any remaining arguments are treated as initial values for the + ## hash that is used to represent this object. Note that we default + ## certain values by specifying them *before* the arguments passed. + ## If they are in the argument list, they will override the defaults. + my $self = { -name => '(unknown)', + -handle => undef, + -was_cutting => 0, + @_ }; + + ## Bless ourselves into the desired class and perform any initialization + bless $self, $class; + return $self; +} + +##--------------------------------------------------------------------------- + +=begin __PRIVATE__ + +=head2 B<name()> + + my $filename = $pod_input->name(); + $pod_input->name($new_filename_to_use); + +This method gets/sets the name of the input source (usually a filename). +If no argument is given, it returns a string containing the name of +the input source; otherwise it sets the name of the input source to the +contents of the given argument. + +=end __PRIVATE__ + +=cut + +sub name { + (@_ > 1) and $_[0]->{'-name'} = $_[1]; + return $_[0]->{'-name'}; +} + +## allow 'filename' as an alias for 'name' +*filename = \&name; + +##--------------------------------------------------------------------------- + +=begin __PRIVATE__ + +=head2 B<handle()> + + my $handle = $pod_input->handle(); + +Returns a reference to the handle object from which input is read (the +one used to contructed this input source object). + +=end __PRIVATE__ + +=cut + +sub handle { + return $_[0]->{'-handle'}; +} + +##--------------------------------------------------------------------------- + +=begin __PRIVATE__ + +=head2 B<was_cutting()> + + print "Yes.\n" if ($pod_input->was_cutting()); + +The value of the C<cutting> state (that the B<cutting()> method would +have returned) immediately before any input was read from this input +stream. After all input from this stream has been read, the C<cutting> +state is restored to this value. + +=end __PRIVATE__ + +=cut + +sub was_cutting { + (@_ > 1) and $_[0]->{-was_cutting} = $_[1]; + return $_[0]->{-was_cutting}; +} + +##--------------------------------------------------------------------------- + +############################################################################# + +package Pod::Paragraph; + +##--------------------------------------------------------------------------- + +=head1 B<Pod::Paragraph> + +An object representing a paragraph of POD input text. +It has the following methods/attributes: + +=cut + +##--------------------------------------------------------------------------- + +=head2 B<new()> + + my $pod_para1 = Pod::Paragraph->new(-text => $text); + my $pod_para2 = Pod::Paragraph->new(-name => $cmd, + -text => $text); + my $pod_para3 = new Pod::Paragraph(-text => $text); + my $pod_para4 = new Pod::Paragraph(-name => $cmd, + -text => $text); + my $pod_para5 = Pod::Paragraph->new(-name => $cmd, + -text => $text, + -file => $filename, + -line => $line_number); + +This is a class method that constructs a C<Pod::Paragraph> object and +returns a reference to the new paragraph object. It may be given one or +two keyword arguments. The C<-text> keyword indicates the corresponding +text of the POD paragraph. The C<-name> keyword indicates the name of +the corresponding POD command, such as C<head1> or C<item> (it should +I<not> contain the C<=> prefix); this is needed only if the POD +paragraph corresponds to a command paragraph. The C<-file> and C<-line> +keywords indicate the filename and line number corresponding to the +beginning of the paragraph + +=cut + +sub new { + ## Determine if we were called via an object-ref or a classname + my $this = shift; + my $class = ref($this) || $this; + + ## Any remaining arguments are treated as initial values for the + ## hash that is used to represent this object. Note that we default + ## certain values by specifying them *before* the arguments passed. + ## If they are in the argument list, they will override the defaults. + my $self = { + -name => undef, + -text => (@_ == 1) ? $_[0] : undef, + -file => '<unknown-file>', + -line => 0, + -prefix => '=', + -separator => ' ', + -ptree => [], + @_ + }; + + ## Bless ourselves into the desired class and perform any initialization + bless $self, $class; + return $self; +} + +##--------------------------------------------------------------------------- + +=head2 B<cmd_name()> + + my $para_cmd = $pod_para->cmd_name(); + +If this paragraph is a command paragraph, then this method will return +the name of the command (I<without> any leading C<=> prefix). + +=cut + +sub cmd_name { + (@_ > 1) and $_[0]->{'-name'} = $_[1]; + return $_[0]->{'-name'}; +} + +## let name() be an alias for cmd_name() +*name = \&cmd_name; + +##--------------------------------------------------------------------------- + +=head2 B<text()> + + my $para_text = $pod_para->text(); + +This method will return the corresponding text of the paragraph. + +=cut + +sub text { + (@_ > 1) and $_[0]->{'-text'} = $_[1]; + return $_[0]->{'-text'}; +} + +##--------------------------------------------------------------------------- + +=head2 B<raw_text()> + + my $raw_pod_para = $pod_para->raw_text(); + +This method will return the I<raw> text of the POD paragraph, exactly +as it appeared in the input. + +=cut + +sub raw_text { + return $_[0]->{'-text'} unless (defined $_[0]->{'-name'}); + return $_[0]->{'-prefix'} . $_[0]->{'-name'} . + $_[0]->{'-separator'} . $_[0]->{'-text'}; +} + +##--------------------------------------------------------------------------- + +=head2 B<cmd_prefix()> + + my $prefix = $pod_para->cmd_prefix(); + +If this paragraph is a command paragraph, then this method will return +the prefix used to denote the command (which should be the string "=" +or "=="). + +=cut + +sub cmd_prefix { + return $_[0]->{'-prefix'}; +} + +##--------------------------------------------------------------------------- + +=head2 B<cmd_separator()> + + my $separator = $pod_para->cmd_separator(); + +If this paragraph is a command paragraph, then this method will return +the text used to separate the command name from the rest of the +paragraph (if any). + +=cut + +sub cmd_separator { + return $_[0]->{'-separator'}; +} + +##--------------------------------------------------------------------------- + +=head2 B<parse_tree()> + + my $ptree = $pod_parser->parse_text( $pod_para->text() ); + $pod_para->parse_tree( $ptree ); + $ptree = $pod_para->parse_tree(); + +This method will get/set the corresponding parse-tree of the paragraph's text. + +=cut + +sub parse_tree { + (@_ > 1) and $_[0]->{'-ptree'} = $_[1]; + return $_[0]->{'-ptree'}; +} + +## let ptree() be an alias for parse_tree() +*ptree = \&parse_tree; + +##--------------------------------------------------------------------------- + +=head2 B<file_line()> + + my ($filename, $line_number) = $pod_para->file_line(); + my $position = $pod_para->file_line(); + +Returns the current filename and line number for the paragraph +object. If called in an array context, it returns a list of two +elements: first the filename, then the line number. If called in +a scalar context, it returns a string containing the filename, followed +by a colon (':'), followed by the line number. + +=cut + +sub file_line { + my @loc = ($_[0]->{'-file'} || '<unknown-file>', + $_[0]->{'-line'} || 0); + return (wantarray) ? @loc : join(':', @loc); +} + +##--------------------------------------------------------------------------- + +############################################################################# + +package Pod::InteriorSequence; + +##--------------------------------------------------------------------------- + +=head1 B<Pod::InteriorSequence> + +An object representing a POD interior sequence command. +It has the following methods/attributes: + +=cut + +##--------------------------------------------------------------------------- + +=head2 B<new()> + + my $pod_seq1 = Pod::InteriorSequence->new(-name => $cmd + -ldelim => $delimiter); + my $pod_seq2 = new Pod::InteriorSequence(-name => $cmd, + -ldelim => $delimiter); + my $pod_seq3 = new Pod::InteriorSequence(-name => $cmd, + -ldelim => $delimiter, + -file => $filename, + -line => $line_number); + +This is a class method that constructs a C<Pod::InteriorSequence> object +and returns a reference to the new interior sequence object. It should +be given two keyword arguments. The C<-ldelim> keyword indicates the +corresponding left-delimiter of the interior sequence (e.g. 'E<lt>'). +The C<-name> keyword indicates the name of the corresponding interior +sequence command, such as C<I> or C<B> or C<C>. The C<-file> and +C<-line> keywords indicate the filename and line number corresponding +to the beginning of the interior sequence. + +=cut + +sub new { + ## Determine if we were called via an object-ref or a classname + my $this = shift; + my $class = ref($this) || $this; + + ## Any remaining arguments are treated as initial values for the + ## hash that is used to represent this object. Note that we default + ## certain values by specifying them *before* the arguments passed. + ## If they are in the argument list, they will override the defaults. + my $self = { + -name => (@_ == 1) ? $_[0] : undef, + -file => '<unknown-file>', + -line => 0, + -ldelim => '<', + -rdelim => '>', + -ptree => new Pod::ParseTree(), + @_ + }; + + ## Bless ourselves into the desired class and perform any initialization + bless $self, $class; + return $self; +} + +##--------------------------------------------------------------------------- + +=head2 B<cmd_name()> + + my $seq_cmd = $pod_seq->cmd_name(); + +The name of the interior sequence command. + +=cut + +sub cmd_name { + (@_ > 1) and $_[0]->{'-name'} = $_[1]; + return $_[0]->{'-name'}; +} + +## let name() be an alias for cmd_name() +*name = \&cmd_name; + +##--------------------------------------------------------------------------- + +## Private subroutine to set the parent pointer of all the given +## children that are interior-sequences to be $self + +sub _set_child2parent_links { + my ($self, @children) = @_; + ## Make sure any sequences know who their parent is + for (@children) { + next unless ref $_; + if ($_->isa('Pod::InteriorSequence') or $_->can('nested')) { + $_->nested($self); + } + } +} + +## Private subroutine to unset child->parent links + +sub _unset_child2parent_links { + my $self = shift; + $self->{'-parent_sequence'} = undef; + my $ptree = $self->{'-ptree'}; + for (@$ptree) { + next unless ($_ and ref $_ and $_->isa('Pod::InteriorSequence')); + $_->_unset_child2parent_links(); + } +} + +##--------------------------------------------------------------------------- + +=head2 B<prepend()> + + $pod_seq->prepend($text); + $pod_seq1->prepend($pod_seq2); + +Prepends the given string or parse-tree or sequence object to the parse-tree +of this interior sequence. + +=cut + +sub prepend { + my $self = shift; + $self->{'-ptree'}->prepend(@_); + _set_child2parent_links($self, @_); + return $self; +} + +##--------------------------------------------------------------------------- + +=head2 B<append()> + + $pod_seq->append($text); + $pod_seq1->append($pod_seq2); + +Appends the given string or parse-tree or sequence object to the parse-tree +of this interior sequence. + +=cut + +sub append { + my $self = shift; + $self->{'-ptree'}->append(@_); + _set_child2parent_links($self, @_); + return $self; +} + +##--------------------------------------------------------------------------- + +=head2 B<nested()> + + $outer_seq = $pod_seq->nested || print "not nested"; + +If this interior sequence is nested inside of another interior +sequence, then the outer/parent sequence that contains it is +returned. Otherwise C<undef> is returned. + +=cut + +sub nested { + my $self = shift; + (@_ == 1) and $self->{'-parent_sequence'} = shift; + return $self->{'-parent_sequence'} || undef; +} + +##--------------------------------------------------------------------------- + +=head2 B<raw_text()> + + my $seq_raw_text = $pod_seq->raw_text(); + +This method will return the I<raw> text of the POD interior sequence, +exactly as it appeared in the input. + +=cut + +sub raw_text { + my $self = shift; + my $text = $self->{'-name'} . $self->{'-ldelim'}; + for ( $self->{'-ptree'}->children ) { + $text .= (ref $_) ? $_->raw_text : $_; + } + $text .= $self->{'-rdelim'}; + return $text; +} + +##--------------------------------------------------------------------------- + +=head2 B<left_delimiter()> + + my $ldelim = $pod_seq->left_delimiter(); + +The leftmost delimiter beginning the argument text to the interior +sequence (should be "<"). + +=cut + +sub left_delimiter { + (@_ > 1) and $_[0]->{'-ldelim'} = $_[1]; + return $_[0]->{'-ldelim'}; +} + +## let ldelim() be an alias for left_delimiter() +*ldelim = \&left_delimiter; + +##--------------------------------------------------------------------------- + +=head2 B<right_delimiter()> + +The rightmost delimiter beginning the argument text to the interior +sequence (should be ">"). + +=cut + +sub right_delimiter { + (@_ > 1) and $_[0]->{'-rdelim'} = $_[1]; + return $_[0]->{'-rdelim'}; +} + +## let rdelim() be an alias for right_delimiter() +*rdelim = \&right_delimiter; + +##--------------------------------------------------------------------------- + +=head2 B<parse_tree()> + + my $ptree = $pod_parser->parse_text($paragraph_text); + $pod_seq->parse_tree( $ptree ); + $ptree = $pod_seq->parse_tree(); + +This method will get/set the corresponding parse-tree of the interior +sequence's text. + +=cut + +sub parse_tree { + (@_ > 1) and $_[0]->{'-ptree'} = $_[1]; + return $_[0]->{'-ptree'}; +} + +## let ptree() be an alias for parse_tree() +*ptree = \&parse_tree; + +##--------------------------------------------------------------------------- + +=head2 B<file_line()> + + my ($filename, $line_number) = $pod_seq->file_line(); + my $position = $pod_seq->file_line(); + +Returns the current filename and line number for the interior sequence +object. If called in an array context, it returns a list of two +elements: first the filename, then the line number. If called in +a scalar context, it returns a string containing the filename, followed +by a colon (':'), followed by the line number. + +=cut + +sub file_line { + my @loc = ($_[0]->{'-file'} || '<unknown-file>', + $_[0]->{'-line'} || 0); + return (wantarray) ? @loc : join(':', @loc); +} + +##--------------------------------------------------------------------------- + +=head2 B<DESTROY()> + +This method performs any necessary cleanup for the interior-sequence. +If you override this method then it is B<imperative> that you invoke +the parent method from within your own method, otherwise +I<interior-sequence storage will not be reclaimed upon destruction!> + +=cut + +sub DESTROY { + ## We need to get rid of all child->parent pointers throughout the + ## tree so their reference counts will go to zero and they can be + ## garbage-collected + _unset_child2parent_links(@_); +} + +##--------------------------------------------------------------------------- + +############################################################################# + +package Pod::ParseTree; + +##--------------------------------------------------------------------------- + +=head1 B<Pod::ParseTree> + +This object corresponds to a tree of parsed POD text. As POD text is +scanned from left to right, it is parsed into an ordered list of +text-strings and B<Pod::InteriorSequence> objects (in order of +appearance). A B<Pod::ParseTree> object corresponds to this list of +strings and sequences. Each interior sequence in the parse-tree may +itself contain a parse-tree (since interior sequences may be nested). + +=cut + +##--------------------------------------------------------------------------- + +=head2 B<new()> + + my $ptree1 = Pod::ParseTree->new; + my $ptree2 = new Pod::ParseTree; + my $ptree4 = Pod::ParseTree->new($array_ref); + my $ptree3 = new Pod::ParseTree($array_ref); + +This is a class method that constructs a C<Pod::Parse_tree> object and +returns a reference to the new parse-tree. If a single-argument is given, +it mist be a reference to an array, and is used to initialize the root +(top) of the parse tree. + +=cut + +sub new { + ## Determine if we were called via an object-ref or a classname + my $this = shift; + my $class = ref($this) || $this; + + my $self = (@_ == 1 and ref $_[0]) ? $_[0] : []; + + ## Bless ourselves into the desired class and perform any initialization + bless $self, $class; + return $self; +} + +##--------------------------------------------------------------------------- + +=head2 B<top()> + + my $top_node = $ptree->top(); + $ptree->top( $top_node ); + $ptree->top( @children ); + +This method gets/sets the top node of the parse-tree. If no arguments are +given, it returns the topmost node in the tree (the root), which is also +a B<Pod::ParseTree>. If it is given a single argument that is a reference, +then the reference is assumed to a parse-tree and becomes the new top node. +Otherwise, if arguments are given, they are treated as the new list of +children for the top node. + +=cut + +sub top { + my $self = shift; + if (@_ > 0) { + @{ $self } = (@_ == 1 and ref $_[0]) ? ${ @_ } : @_; + } + return $self; +} + +## let parse_tree() & ptree() be aliases for the 'top' method +*parse_tree = *ptree = \⊤ + +##--------------------------------------------------------------------------- + +=head2 B<children()> + +This method gets/sets the children of the top node in the parse-tree. +If no arguments are given, it returns the list (array) of children +(each of which should be either a string or a B<Pod::InteriorSequence>. +Otherwise, if arguments are given, they are treated as the new list of +children for the top node. + +=cut + +sub children { + my $self = shift; + if (@_ > 0) { + @{ $self } = (@_ == 1 and ref $_[0]) ? ${ @_ } : @_; + } + return @{ $self }; +} + +##--------------------------------------------------------------------------- + +=head2 B<prepend()> + +This method prepends the given text or parse-tree to the current parse-tree. +If the first item on the parse-tree is text and the argument is also text, +then the text is prepended to the first item (not added as a separate string). +Otherwise the argument is added as a new string or parse-tree I<before> +the current one. + +=cut + +use vars qw(@ptree); ## an alias used for performance reasons + +sub prepend { + my $self = shift; + local *ptree = $self; + for (@_) { + next unless $_; + if (@ptree and !(ref $ptree[0]) and !(ref $_)) { + $ptree[0] = $_ . $ptree[0]; + } + else { + unshift @ptree, $_; + } + } +} + +##--------------------------------------------------------------------------- + +=head2 B<append()> + +This method appends the given text or parse-tree to the current parse-tree. +If the last item on the parse-tree is text and the argument is also text, +then the text is appended to the last item (not added as a separate string). +Otherwise the argument is added as a new string or parse-tree I<after> +the current one. + +=cut + +sub append { + my $self = shift; + local *ptree = $self; + for (@_) { + next unless $_; + if (@ptree and !(ref $ptree[-1]) and !(ref $_)) { + $ptree[-1] .= $_; + } + else { + push @ptree, $_; + } + } +} + +=head2 B<raw_text()> + + my $ptree_raw_text = $ptree->raw_text(); + +This method will return the I<raw> text of the POD parse-tree +exactly as it appeared in the input. + +=cut + +sub raw_text { + my $self = shift; + my $text = ""; + for ( @$self ) { + $text .= (ref $_) ? $_->raw_text : $_; + } + return $text; +} + +##--------------------------------------------------------------------------- + +## Private routines to set/unset child->parent links + +sub _unset_child2parent_links { + my $self = shift; + local *ptree = $self; + for (@ptree) { + next unless ($_ and ref $_ and $_->isa('Pod::InteriorSequence')); + $_->_unset_child2parent_links(); + } +} + +sub _set_child2parent_links { + ## nothing to do, Pod::ParseTrees cant have parent pointers +} + +=head2 B<DESTROY()> + +This method performs any necessary cleanup for the parse-tree. +If you override this method then it is B<imperative> +that you invoke the parent method from within your own method, +otherwise I<parse-tree storage will not be reclaimed upon destruction!> + +=cut + +sub DESTROY { + ## We need to get rid of all child->parent pointers throughout the + ## tree so their reference counts will go to zero and they can be + ## garbage-collected + _unset_child2parent_links(@_); +} + +############################################################################# + +=head1 SEE ALSO + +See L<Pod::Parser>, L<Pod::Select>, and L<Pod::Callbacks>. + +=head1 AUTHOR + +Brad Appleton E<lt>bradapp@enteract.comE<gt> + +=cut + +1; |