1# Pod::PlainText -- Convert POD data to formatted ASCII text.
2# $Id: Text.pm,v 2.1 1999/09/20 11:53:33 eagle Exp $
3#
4# Copyright 1999-2000 by Russ Allbery <rra@stanford.edu>
5#
6# This program is free software; you can redistribute it and/or modify it
7# under the same terms as Perl itself.
8#
9# This module is intended to be a replacement for Pod::Text, and attempts to
10# match its output except for some specific circumstances where other
11# decisions seemed to produce better output.  It uses Pod::Parser and is
12# designed to be very easy to subclass.
13
14############################################################################
15# Modules and declarations
16############################################################################
17
18package Pod::PlainText;
19use strict;
20
21require 5.005;
22
23use Carp qw(carp croak);
24use Pod::Select ();
25
26use vars qw(@ISA %ESCAPES $VERSION);
27
28# We inherit from Pod::Select instead of Pod::Parser so that we can be used
29# by Pod::Usage.
30@ISA = qw(Pod::Select);
31
32$VERSION = '2.04';
33
34BEGIN {
35   if ($] < 5.006) {
36      require Symbol;
37      import Symbol;
38   }
39}
40
41############################################################################
42# Table of supported E<> escapes
43############################################################################
44
45# This table is taken near verbatim from Pod::PlainText in Pod::Parser,
46# which got it near verbatim from the original Pod::Text.  It is therefore
47# credited to Tom Christiansen, and I'm glad I didn't have to write it.  :)
48%ESCAPES = (
49    'amp'       =>    '&',      # ampersand
50    'lt'        =>    '<',      # left chevron, less-than
51    'gt'        =>    '>',      # right chevron, greater-than
52    'quot'      =>    '"',      # double quote
53
54    "Aacute"    =>    "\xC1",   # capital A, acute accent
55    "aacute"    =>    "\xE1",   # small a, acute accent
56    "Acirc"     =>    "\xC2",   # capital A, circumflex accent
57    "acirc"     =>    "\xE2",   # small a, circumflex accent
58    "AElig"     =>    "\xC6",   # capital AE diphthong (ligature)
59    "aelig"     =>    "\xE6",   # small ae diphthong (ligature)
60    "Agrave"    =>    "\xC0",   # capital A, grave accent
61    "agrave"    =>    "\xE0",   # small a, grave accent
62    "Aring"     =>    "\xC5",   # capital A, ring
63    "aring"     =>    "\xE5",   # small a, ring
64    "Atilde"    =>    "\xC3",   # capital A, tilde
65    "atilde"    =>    "\xE3",   # small a, tilde
66    "Auml"      =>    "\xC4",   # capital A, dieresis or umlaut mark
67    "auml"      =>    "\xE4",   # small a, dieresis or umlaut mark
68    "Ccedil"    =>    "\xC7",   # capital C, cedilla
69    "ccedil"    =>    "\xE7",   # small c, cedilla
70    "Eacute"    =>    "\xC9",   # capital E, acute accent
71    "eacute"    =>    "\xE9",   # small e, acute accent
72    "Ecirc"     =>    "\xCA",   # capital E, circumflex accent
73    "ecirc"     =>    "\xEA",   # small e, circumflex accent
74    "Egrave"    =>    "\xC8",   # capital E, grave accent
75    "egrave"    =>    "\xE8",   # small e, grave accent
76    "ETH"       =>    "\xD0",   # capital Eth, Icelandic
77    "eth"       =>    "\xF0",   # small eth, Icelandic
78    "Euml"      =>    "\xCB",   # capital E, dieresis or umlaut mark
79    "euml"      =>    "\xEB",   # small e, dieresis or umlaut mark
80    "Iacute"    =>    "\xCD",   # capital I, acute accent
81    "iacute"    =>    "\xED",   # small i, acute accent
82    "Icirc"     =>    "\xCE",   # capital I, circumflex accent
83    "icirc"     =>    "\xEE",   # small i, circumflex accent
84    "Igrave"    =>    "\xCD",   # capital I, grave accent
85    "igrave"    =>    "\xED",   # small i, grave accent
86    "Iuml"      =>    "\xCF",   # capital I, dieresis or umlaut mark
87    "iuml"      =>    "\xEF",   # small i, dieresis or umlaut mark
88    "Ntilde"    =>    "\xD1",   # capital N, tilde
89    "ntilde"    =>    "\xF1",   # small n, tilde
90    "Oacute"    =>    "\xD3",   # capital O, acute accent
91    "oacute"    =>    "\xF3",   # small o, acute accent
92    "Ocirc"     =>    "\xD4",   # capital O, circumflex accent
93    "ocirc"     =>    "\xF4",   # small o, circumflex accent
94    "Ograve"    =>    "\xD2",   # capital O, grave accent
95    "ograve"    =>    "\xF2",   # small o, grave accent
96    "Oslash"    =>    "\xD8",   # capital O, slash
97    "oslash"    =>    "\xF8",   # small o, slash
98    "Otilde"    =>    "\xD5",   # capital O, tilde
99    "otilde"    =>    "\xF5",   # small o, tilde
100    "Ouml"      =>    "\xD6",   # capital O, dieresis or umlaut mark
101    "ouml"      =>    "\xF6",   # small o, dieresis or umlaut mark
102    "szlig"     =>    "\xDF",   # small sharp s, German (sz ligature)
103    "THORN"     =>    "\xDE",   # capital THORN, Icelandic
104    "thorn"     =>    "\xFE",   # small thorn, Icelandic
105    "Uacute"    =>    "\xDA",   # capital U, acute accent
106    "uacute"    =>    "\xFA",   # small u, acute accent
107    "Ucirc"     =>    "\xDB",   # capital U, circumflex accent
108    "ucirc"     =>    "\xFB",   # small u, circumflex accent
109    "Ugrave"    =>    "\xD9",   # capital U, grave accent
110    "ugrave"    =>    "\xF9",   # small u, grave accent
111    "Uuml"      =>    "\xDC",   # capital U, dieresis or umlaut mark
112    "uuml"      =>    "\xFC",   # small u, dieresis or umlaut mark
113    "Yacute"    =>    "\xDD",   # capital Y, acute accent
114    "yacute"    =>    "\xFD",   # small y, acute accent
115    "yuml"      =>    "\xFF",   # small y, dieresis or umlaut mark
116
117    "lchevron"  =>    "\xAB",   # left chevron (double less than)
118    "rchevron"  =>    "\xBB",   # right chevron (double greater than)
119);
120
121
122############################################################################
123# Initialization
124############################################################################
125
126# Initialize the object.  Must be sure to call our parent initializer.
127sub initialize {
128    my $self = shift;
129
130    $$self{alt}      = 0  unless defined $$self{alt};
131    $$self{indent}   = 4  unless defined $$self{indent};
132    $$self{loose}    = 0  unless defined $$self{loose};
133    $$self{sentence} = 0  unless defined $$self{sentence};
134    $$self{width}    = 76 unless defined $$self{width};
135
136    $$self{INDENTS}  = [];              # Stack of indentations.
137    $$self{MARGIN}   = $$self{indent};  # Current left margin in spaces.
138
139    return $self->SUPER::initialize;
140}
141
142
143############################################################################
144# Core overrides
145############################################################################
146
147# Called for each command paragraph.  Gets the command, the associated
148# paragraph, the line number, and a Pod::Paragraph object.  Just dispatches
149# the command to a method named the same as the command.  =cut is handled
150# internally by Pod::Parser.
151sub command {
152    my $self = shift;
153    my $command = shift;
154    return if $command eq 'pod';
155    return if ($$self{EXCLUDE} && $command ne 'end');
156    if (defined $$self{ITEM}) {
157      $self->item ("\n");
158      local $_ = "\n";
159      $self->output($_) if($command eq 'back');
160    }
161    $command = 'cmd_' . $command;
162    return $self->$command (@_);
163}
164
165# Called for a verbatim paragraph.  Gets the paragraph, the line number, and
166# a Pod::Paragraph object.  Just output it verbatim, but with tabs converted
167# to spaces.
168sub verbatim {
169    my $self = shift;
170    return if $$self{EXCLUDE};
171    $self->item if defined $$self{ITEM};
172    local $_ = shift;
173    return if /^\s*$/;
174    s/^(\s*\S+)/(' ' x $$self{MARGIN}) . $1/gme;
175    return $self->output($_);
176}
177
178# Called for a regular text block.  Gets the paragraph, the line number, and
179# a Pod::Paragraph object.  Perform interpolation and output the results.
180sub textblock {
181    my $self = shift;
182    return if $$self{EXCLUDE};
183    if($$self{VERBATIM}) {
184      $self->output($_[0]);
185      return;
186    }
187    local $_ = shift;
188    my $line = shift;
189
190    # Perform a little magic to collapse multiple L<> references.  This is
191    # here mostly for backwards-compatibility.  We'll just rewrite the whole
192    # thing into actual text at this part, bypassing the whole internal
193    # sequence parsing thing.
194    s{
195        (
196          L<                    # A link of the form L</something>.
197              /
198              (
199                  [:\w]+        # The item has to be a simple word...
200                  (\(\))?       # ...or simple function.
201              )
202          >
203          (
204              ,?\s+(and\s+)?    # Allow lots of them, conjuncted.
205              L<
206                  /
207                  (
208                      [:\w]+
209                      (\(\))?
210                  )
211              >
212          )+
213        )
214    } {
215        local $_ = $1;
216        s%L</([^>]+)>%$1%g;
217        my @items = split /(?:,?\s+(?:and\s+)?)/;
218        my $string = "the ";
219        my $i;
220        for ($i = 0; $i < @items; $i++) {
221            $string .= $items[$i];
222            $string .= ", " if @items > 2 && $i != $#items;
223            $string .= " and " if ($i == $#items - 1);
224        }
225        $string .= " entries elsewhere in this document";
226        $string;
227    }gex;
228
229    # Now actually interpolate and output the paragraph.
230    $_ = $self->interpolate ($_, $line);
231    s/\s*$/\n/s;
232    if (defined $$self{ITEM}) {
233        $self->item ($_ . "\n");
234    } else {
235        $self->output ($self->reformat ($_ . "\n"));
236    }
237}
238
239# Called for an interior sequence.  Gets the command, argument, and a
240# Pod::InteriorSequence object and is expected to return the resulting text.
241# Calls code, bold, italic, file, and link to handle those types of
242# sequences, and handles S<>, E<>, X<>, and Z<> directly.
243sub interior_sequence {
244    my $self = shift;
245    my $command = shift;
246    local $_ = shift;
247    return '' if ($command eq 'X' || $command eq 'Z');
248
249    # Expand escapes into the actual character now, carping if invalid.
250    if ($command eq 'E') {
251        return $ESCAPES{$_} if defined $ESCAPES{$_};
252        carp "Unknown escape: E<$_>";
253        return "E<$_>";
254    }
255
256    # For all the other sequences, empty content produces no output.
257    return if $_ eq '';
258
259    # For S<>, compress all internal whitespace and then map spaces to \01.
260    # When we output the text, we'll map this back.
261    if ($command eq 'S') {
262        s/\s{2,}/ /g;
263        tr/ /\01/;
264        return $_;
265    }
266
267    # Anything else needs to get dispatched to another method.
268    if    ($command eq 'B') { return $self->seq_b ($_) }
269    elsif ($command eq 'C') { return $self->seq_c ($_) }
270    elsif ($command eq 'F') { return $self->seq_f ($_) }
271    elsif ($command eq 'I') { return $self->seq_i ($_) }
272    elsif ($command eq 'L') { return $self->seq_l ($_) }
273    else { carp "Unknown sequence $command<$_>" }
274}
275
276# Called for each paragraph that's actually part of the POD.  We take
277# advantage of this opportunity to untabify the input.
278sub preprocess_paragraph {
279    my $self = shift;
280    local $_ = shift;
281    1 while s/^(.*?)(\t+)/$1 . ' ' x (length ($2) * 8 - length ($1) % 8)/me;
282    return $_;
283}
284
285
286############################################################################
287# Command paragraphs
288############################################################################
289
290# All command paragraphs take the paragraph and the line number.
291
292# First level heading.
293sub cmd_head1 {
294    my $self = shift;
295    local $_ = shift;
296    s/\s+$//s;
297    $_ = $self->interpolate ($_, shift);
298    if ($$self{alt}) {
299        $self->output ("\n==== $_ ====\n\n");
300    } else {
301        $_ .= "\n" if $$self{loose};
302        $self->output ($_ . "\n");
303    }
304}
305
306# Second level heading.
307sub cmd_head2 {
308    my $self = shift;
309    local $_ = shift;
310    s/\s+$//s;
311    $_ = $self->interpolate ($_, shift);
312    if ($$self{alt}) {
313        $self->output ("\n==   $_   ==\n\n");
314    } else {
315        $_ .= "\n" if $$self{loose};
316        $self->output (' ' x ($$self{indent} / 2) . $_ . "\n");
317    }
318}
319
320# third level heading - not strictly perlpodspec compliant
321sub cmd_head3 {
322    my $self = shift;
323    local $_ = shift;
324    s/\s+$//s;
325    $_ = $self->interpolate ($_, shift);
326    if ($$self{alt}) {
327        $self->output ("\n= $_ =\n");
328    } else {
329        $_ .= "\n" if $$self{loose};
330        $self->output (' ' x ($$self{indent}) . $_ . "\n");
331    }
332}
333
334# fourth level heading - not strictly perlpodspec compliant
335# just like head3
336*cmd_head4 = \&cmd_head3;
337
338# Start a list.
339sub cmd_over {
340    my $self = shift;
341    local $_ = shift;
342    unless (/^[-+]?\d+\s+$/) { $_ = $$self{indent} }
343    push (@{ $$self{INDENTS} }, $$self{MARGIN});
344    $$self{MARGIN} += ($_ + 0);
345}
346
347# End a list.
348sub cmd_back {
349    my $self = shift;
350    $$self{MARGIN} = pop @{ $$self{INDENTS} };
351    unless (defined $$self{MARGIN}) {
352        carp 'Unmatched =back';
353        $$self{MARGIN} = $$self{indent};
354    }
355}
356
357# An individual list item.
358sub cmd_item {
359    my $self = shift;
360    if (defined $$self{ITEM}) { $self->item }
361    local $_ = shift;
362    s/\s+$//s;
363    $$self{ITEM} = $self->interpolate ($_);
364}
365
366# Begin a block for a particular translator.  Setting VERBATIM triggers
367# special handling in textblock().
368sub cmd_begin {
369    my $self = shift;
370    local $_ = shift;
371    my ($kind) = /^(\S+)/ or return;
372    if ($kind eq 'text') {
373        $$self{VERBATIM} = 1;
374    } else {
375        $$self{EXCLUDE} = 1;
376    }
377}
378
379# End a block for a particular translator.  We assume that all =begin/=end
380# pairs are properly closed.
381sub cmd_end {
382    my $self = shift;
383    $$self{EXCLUDE} = 0;
384    $$self{VERBATIM} = 0;
385}
386
387# One paragraph for a particular translator.  Ignore it unless it's intended
388# for text, in which case we treat it as a verbatim text block.
389sub cmd_for {
390    my $self = shift;
391    local $_ = shift;
392    my $line = shift;
393    return unless s/^text\b[ \t]*\n?//;
394    $self->verbatim ($_, $line);
395}
396
397
398############################################################################
399# Interior sequences
400############################################################################
401
402# The simple formatting ones.  These are here mostly so that subclasses can
403# override them and do more complicated things.
404sub seq_b { return $_[0]{alt} ? "``$_[1]''" : $_[1] }
405sub seq_c { return $_[0]{alt} ? "``$_[1]''" : "`$_[1]'" }
406sub seq_f { return $_[0]{alt} ? "\"$_[1]\"" : $_[1] }
407sub seq_i { return '*' . $_[1] . '*' }
408
409# The complicated one.  Handle links.  Since this is plain text, we can't
410# actually make any real links, so this is all to figure out what text we
411# print out.
412sub seq_l {
413    my $self = shift;
414    local $_ = shift;
415
416    # Smash whitespace in case we were split across multiple lines.
417    s/\s+/ /g;
418
419    # If we were given any explicit text, just output it.
420    if (/^([^|]+)\|/) { return $1 }
421
422    # Okay, leading and trailing whitespace isn't important; get rid of it.
423    s/^\s+//;
424    s/\s+$//;
425
426    # Default to using the whole content of the link entry as a section
427    # name.  Note that L<manpage/> forces a manpage interpretation, as does
428    # something looking like L<manpage(section)>.  The latter is an
429    # enhancement over the original Pod::Text.
430    my ($manpage, $section) = ('', $_);
431    if (/^(?:https?|ftp|news):/) {
432        # a URL
433        return $_;
434    } elsif (/^"\s*(.*?)\s*"$/) {
435        $section = '"' . $1 . '"';
436    } elsif (m/^[-:.\w]+(?:\(\S+\))?$/) {
437        ($manpage, $section) = ($_, '');
438    } elsif (m{/}) {
439        ($manpage, $section) = split (/\s*\/\s*/, $_, 2);
440    }
441
442    my $text = '';
443    # Now build the actual output text.
444    if (!length $section) {
445        $text = "the $manpage manpage" if length $manpage;
446    } elsif ($section =~ /^[:\w]+(?:\(\))?/) {
447        $text .= 'the ' . $section . ' entry';
448        $text .= (length $manpage) ? " in the $manpage manpage"
449                                   : ' elsewhere in this document';
450    } else {
451        $section =~ s/^\"\s*//;
452        $section =~ s/\s*\"$//;
453        $text .= 'the section on "' . $section . '"';
454        $text .= " in the $manpage manpage" if length $manpage;
455    }
456    return $text;
457}
458
459
460############################################################################
461# List handling
462############################################################################
463
464# This method is called whenever an =item command is complete (in other
465# words, we've seen its associated paragraph or know for certain that it
466# doesn't have one).  It gets the paragraph associated with the item as an
467# argument.  If that argument is empty, just output the item tag; if it
468# contains a newline, output the item tag followed by the newline.
469# Otherwise, see if there's enough room for us to output the item tag in the
470# margin of the text or if we have to put it on a separate line.
471sub item {
472    my $self = shift;
473    local $_ = shift;
474    my $tag = $$self{ITEM};
475    unless (defined $tag) {
476        carp 'item called without tag';
477        return;
478    }
479    undef $$self{ITEM};
480    my $indent = $$self{INDENTS}[-1];
481    unless (defined $indent) { $indent = $$self{indent} }
482    my $space = ' ' x $indent;
483    $space =~ s/^ /:/ if $$self{alt};
484    if (!$_ || /^\s+$/ || ($$self{MARGIN} - $indent < length ($tag) + 1)) {
485        my $margin = $$self{MARGIN};
486        $$self{MARGIN} = $indent;
487        my $output = $self->reformat ($tag);
488        $output =~ s/\n*$/\n/;
489        $self->output ($output);
490        $$self{MARGIN} = $margin;
491        $self->output ($self->reformat ($_)) if /\S/;
492    } else {
493        $_ = $self->reformat ($_);
494        s/^ /:/ if ($$self{alt} && $indent > 0);
495        my $tagspace = ' ' x length $tag;
496        s/^($space)$tagspace/$1$tag/ or carp 'Bizarre space in item';
497        $self->output ($_);
498    }
499}
500
501
502############################################################################
503# Output formatting
504############################################################################
505
506# Wrap a line, indenting by the current left margin.  We can't use
507# Text::Wrap because it plays games with tabs.  We can't use formline, even
508# though we'd really like to, because it screws up non-printing characters.
509# So we have to do the wrapping ourselves.
510sub wrap {
511    my $self = shift;
512    local $_ = shift;
513    my $output = '';
514    my $spaces = ' ' x $$self{MARGIN};
515    my $width = $$self{width} - $$self{MARGIN};
516    while (length > $width) {
517        if (s/^([^\n]{0,$width})\s+// || s/^([^\n]{$width})//) {
518            $output .= $spaces . $1 . "\n";
519        } else {
520            last;
521        }
522    }
523    $output .= $spaces . $_;
524    $output =~ s/\s+$/\n\n/;
525    return $output;
526}
527
528# Reformat a paragraph of text for the current margin.  Takes the text to
529# reformat and returns the formatted text.
530sub reformat {
531    my $self = shift;
532    local $_ = shift;
533
534    # If we're trying to preserve two spaces after sentences, do some
535    # munging to support that.  Otherwise, smash all repeated whitespace.
536    if ($$self{sentence}) {
537        s/ +$//mg;
538        s/\.\n/. \n/g;
539        s/\n/ /g;
540        s/   +/  /g;
541    } else {
542        s/\s+/ /g;
543    }
544    return $self->wrap($_);
545}
546
547# Output text to the output device.
548sub output { $_[1] =~ tr/\01/ /; print { $_[0]->output_handle } $_[1] }
549
550
551############################################################################
552# Backwards compatibility
553############################################################################
554
555# The old Pod::Text module did everything in a pod2text() function.  This
556# tries to provide the same interface for legacy applications.
557sub pod2text {
558    my @args;
559
560    # This is really ugly; I hate doing option parsing in the middle of a
561    # module.  But the old Pod::Text module supported passing flags to its
562    # entry function, so handle -a and -<number>.
563    while ($_[0] =~ /^-/) {
564        my $flag = shift;
565        if    ($flag eq '-a')       { push (@args, alt => 1)    }
566        elsif ($flag =~ /^-(\d+)$/) { push (@args, width => $1) }
567        else {
568            unshift (@_, $flag);
569            last;
570        }
571    }
572
573    # Now that we know what arguments we're using, create the parser.
574    my $parser = Pod::PlainText->new (@args);
575
576    # If two arguments were given, the second argument is going to be a file
577    # handle.  That means we want to call parse_from_filehandle(), which
578    # means we need to turn the first argument into a file handle.  Magic
579    # open will handle the <&STDIN case automagically.
580    if (defined $_[1]) {
581        my $infh;
582        if ($] < 5.006) {
583          $infh = gensym();
584        }
585        unless (open ($infh, $_[0])) {
586            croak ("Can't open $_[0] for reading: $!\n");
587        }
588        $_[0] = $infh;
589        return $parser->parse_from_filehandle (@_);
590    } else {
591        return $parser->parse_from_file (@_);
592    }
593}
594
595
596############################################################################
597# Module return value and documentation
598############################################################################
599
6001;
601__END__
602
603=head1 NAME
604
605Pod::PlainText - Convert POD data to formatted ASCII text
606
607=head1 SYNOPSIS
608
609    use Pod::PlainText;
610    my $parser = Pod::PlainText->new (sentence => 0, width => 78);
611
612    # Read POD from STDIN and write to STDOUT.
613    $parser->parse_from_filehandle;
614
615    # Read POD from file.pod and write to file.txt.
616    $parser->parse_from_file ('file.pod', 'file.txt');
617
618=head1 DESCRIPTION
619
620Pod::PlainText is a module that can convert documentation in the POD format (the
621preferred language for documenting Perl) into formatted ASCII.  It uses no
622special formatting controls or codes whatsoever, and its output is therefore
623suitable for nearly any device.
624
625As a derived class from Pod::Parser, Pod::PlainText supports the same methods and
626interfaces.  See L<Pod::Parser> for all the details; briefly, one creates a
627new parser with C<Pod::PlainText-E<gt>new()> and then calls either
628parse_from_filehandle() or parse_from_file().
629
630new() can take options, in the form of key/value pairs, that control the
631behavior of the parser.  The currently recognized options are:
632
633=over 4
634
635=item alt
636
637If set to a true value, selects an alternate output format that, among other
638things, uses a different heading style and marks C<=item> entries with a
639colon in the left margin.  Defaults to false.
640
641=item indent
642
643The number of spaces to indent regular text, and the default indentation for
644C<=over> blocks.  Defaults to 4.
645
646=item loose
647
648If set to a true value, a blank line is printed after a C<=headN> headings.
649If set to false (the default), no blank line is printed after C<=headN>.
650This is the default because it's the expected formatting for manual pages;
651if you're formatting arbitrary text documents, setting this to true may
652result in more pleasing output.
653
654=item sentence
655
656If set to a true value, Pod::PlainText will assume that each sentence ends in two
657spaces, and will try to preserve that spacing.  If set to false, all
658consecutive whitespace in non-verbatim paragraphs is compressed into a
659single space.  Defaults to true.
660
661=item width
662
663The column at which to wrap text on the right-hand side.  Defaults to 76.
664
665=back
666
667The standard Pod::Parser method parse_from_filehandle() takes up to two
668arguments, the first being the file handle to read POD from and the second
669being the file handle to write the formatted output to.  The first defaults
670to STDIN if not given, and the second defaults to STDOUT.  The method
671parse_from_file() is almost identical, except that its two arguments are the
672input and output disk files instead.  See L<Pod::Parser> for the specific
673details.
674
675=head1 DIAGNOSTICS
676
677=over 4
678
679=item Bizarre space in item
680
681(W) Something has gone wrong in internal C<=item> processing.  This message
682indicates a bug in Pod::PlainText; you should never see it.
683
684=item Can't open %s for reading: %s
685
686(F) Pod::PlainText was invoked via the compatibility mode pod2text() interface
687and the input file it was given could not be opened.
688
689=item Unknown escape: %s
690
691(W) The POD source contained an C<EE<lt>E<gt>> escape that Pod::PlainText didn't
692know about.
693
694=item Unknown sequence: %s
695
696(W) The POD source contained a non-standard internal sequence (something of
697the form C<XE<lt>E<gt>>) that Pod::PlainText didn't know about.
698
699=item Unmatched =back
700
701(W) Pod::PlainText encountered a C<=back> command that didn't correspond to an
702C<=over> command.
703
704=back
705
706=head1 RESTRICTIONS
707
708Embedded Ctrl-As (octal 001) in the input will be mapped to spaces on
709output, due to an internal implementation detail.
710
711=head1 NOTES
712
713This is a replacement for an earlier Pod::Text module written by Tom
714Christiansen.  It has a revamped interface, since it now uses Pod::Parser,
715but an interface roughly compatible with the old Pod::Text::pod2text()
716function is still available.  Please change to the new calling convention,
717though.
718
719The original Pod::Text contained code to do formatting via termcap
720sequences, although it wasn't turned on by default and it was problematic to
721get it to work at all.  This rewrite doesn't even try to do that, but a
722subclass of it does.  Look for L<Pod::Text::Termcap|Pod::Text::Termcap>.
723
724=head1 SEE ALSO
725
726L<Pod::Parser|Pod::Parser>, L<Pod::Text::Termcap|Pod::Text::Termcap>,
727pod2text(1)
728
729=head1 AUTHOR
730
731Please report bugs using L<http://rt.cpan.org>.
732
733Russ Allbery E<lt>rra@stanford.eduE<gt>, based I<very> heavily on the
734original Pod::Text by Tom Christiansen E<lt>tchrist@mox.perl.comE<gt> and
735its conversion to Pod::Parser by Brad Appleton
736E<lt>bradapp@enteract.comE<gt>.
737
738=cut
739