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author | Staszek Wawrykiewicz <staw@gust.org.pl> | 2006-12-18 03:24:34 +0000 |
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committer | Staszek Wawrykiewicz <staw@gust.org.pl> | 2006-12-18 03:24:34 +0000 |
commit | fbf4a6e8014789c67a381e0b4f05de5bdadbce24 (patch) | |
tree | 20cc48dd29799a673fe0a628e825114d823493b1 /Master/perltl/lib/Text/Wrap.pm | |
parent | 34c11d2616bb32772199abf210ae88d99665a824 (diff) |
perltl added
git-svn-id: svn://tug.org/texlive/trunk@2778 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/perltl/lib/Text/Wrap.pm')
-rw-r--r-- | Master/perltl/lib/Text/Wrap.pm | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/Master/perltl/lib/Text/Wrap.pm b/Master/perltl/lib/Text/Wrap.pm new file mode 100644 index 00000000000..8dd1f6c2512 --- /dev/null +++ b/Master/perltl/lib/Text/Wrap.pm @@ -0,0 +1,211 @@ +package Text::Wrap; + +require Exporter; + +@ISA = qw(Exporter); +@EXPORT = qw(wrap fill); +@EXPORT_OK = qw($columns $break $huge); + +$VERSION = 2001.0929; + +use vars qw($VERSION $columns $debug $break $huge $unexpand $tabstop + $separator); +use strict; + +BEGIN { + $columns = 76; # <= screen width + $debug = 0; + $break = '\s'; + $huge = 'wrap'; # alternatively: 'die' or 'overflow' + $unexpand = 1; + $tabstop = 8; + $separator = "\n"; +} + +use Text::Tabs qw(expand unexpand); + +sub wrap +{ + my ($ip, $xp, @t) = @_; + + local($Text::Tabs::tabstop) = $tabstop; + my $r = ""; + my $tail = pop(@t); + my $t = expand(join("", (map { /\s+\z/ ? ( $_ ) : ($_, ' ') } @t), $tail)); + my $lead = $ip; + my $ll = $columns - length(expand($ip)) - 1; + my $nll = $columns - length(expand($xp)) - 1; + my $nl = ""; + my $remainder = ""; + + use re 'taint'; + + pos($t) = 0; + while ($t !~ /\G\s*\Z/gc) { + if ($t =~ /\G([^\n]{0,$ll})($break|\z)/xmgc) { + $r .= $unexpand + ? unexpand($nl . $lead . $1) + : $nl . $lead . $1; + $remainder = $2; + } elsif ($huge eq 'wrap' && $t =~ /\G([^\n]{$ll})/gc) { + $r .= $unexpand + ? unexpand($nl . $lead . $1) + : $nl . $lead . $1; + $remainder = $separator; + } elsif ($huge eq 'overflow' && $t =~ /\G([^\n]*?)($break|\z)/xmgc) { + $r .= $unexpand + ? unexpand($nl . $lead . $1) + : $nl . $lead . $1; + $remainder = $2; + } elsif ($huge eq 'die') { + die "couldn't wrap '$t'"; + } else { + die "This shouldn't happen"; + } + + $lead = $xp; + $ll = $nll; + $nl = $separator; + } + $r .= $remainder; + + print "-----------$r---------\n" if $debug; + + print "Finish up with '$lead'\n" if $debug; + + $r .= $lead . substr($t, pos($t), length($t)-pos($t)) + if pos($t) ne length($t); + + print "-----------$r---------\n" if $debug;; + + return $r; +} + +sub fill +{ + my ($ip, $xp, @raw) = @_; + my @para; + my $pp; + + for $pp (split(/\n\s+/, join("\n",@raw))) { + $pp =~ s/\s+/ /g; + my $x = wrap($ip, $xp, $pp); + push(@para, $x); + } + + # if paragraph_indent is the same as line_indent, + # separate paragraphs with blank lines + + my $ps = ($ip eq $xp) ? "\n\n" : "\n"; + return join ($ps, @para); +} + +1; +__END__ + +=head1 NAME + +Text::Wrap - line wrapping to form simple paragraphs + +=head1 SYNOPSIS + +B<Example 1> + + use Text::Wrap + + $initial_tab = "\t"; # Tab before first line + $subsequent_tab = ""; # All other lines flush left + + print wrap($initial_tab, $subsequent_tab, @text); + print fill($initial_tab, $subsequent_tab, @text); + + @lines = wrap($initial_tab, $subsequent_tab, @text); + + @paragraphs = fill($initial_tab, $subsequent_tab, @text); + +B<Example 2> + + use Text::Wrap qw(wrap $columns $huge); + + $columns = 132; # Wrap at 132 characters + $huge = 'die'; + $huge = 'wrap'; + $huge = 'overflow'; + +B<Example 3> + + use Text::Wrap + + $Text::Wrap::columns = 72; + print wrap('', '', @text); + +=head1 DESCRIPTION + +C<Text::Wrap::wrap()> is a very simple paragraph formatter. It formats a +single paragraph at a time by breaking lines at word boundries. +Indentation is controlled for the first line (C<$initial_tab>) and +all subsquent lines (C<$subsequent_tab>) independently. Please note: +C<$initial_tab> and C<$subsequent_tab> are the literal strings that will +be used: it is unlikley you would want to pass in a number. + +Text::Wrap::fill() is a simple multi-paragraph formatter. It formats +each paragraph separately and then joins them together when it's done. It +will destory any whitespace in the original text. It breaks text into +paragraphs by looking for whitespace after a newline. In other respects +it acts like wrap(). + +=head1 OVERRIDES + +C<Text::Wrap::wrap()> has a number of variables that control its behavior. +Because other modules might be using C<Text::Wrap::wrap()> it is suggested +that you leave these variables alone! If you can't do that, then +use C<local($Text::Wrap::VARIABLE) = YOURVALUE> when you change the +values so that the original value is restored. This C<local()> trick +will not work if you import the variable into your own namespace. + +Lines are wrapped at C<$Text::Wrap::columns> columns. C<$Text::Wrap::columns> +should be set to the full width of your output device. In fact, +every resulting line will have length of no more than C<$columns - 1>. + +It is possible to control which characters terminate words by +modifying C<$Text::Wrap::break>. Set this to a string such as +C<'[\s:]'> (to break before spaces or colons) or a pre-compiled regexp +such as C<qr/[\s']/> (to break before spaces or apostrophes). The +default is simply C<'\s'>; that is, words are terminated by spaces. +(This means, among other things, that trailing punctuation such as +full stops or commas stay with the word they are "attached" to.) + +Beginner note: In example 2, above C<$columns> is imported into +the local namespace, and set locally. In example 3, +C<$Text::Wrap::columns> is set in its own namespace without importing it. + +C<Text::Wrap::wrap()> starts its work by expanding all the tabs in its +input into spaces. The last thing it does it to turn spaces back +into tabs. If you do not want tabs in your results, set +C<$Text::Wrap::unexapand> to a false value. Likewise if you do not +want to use 8-character tabstops, set C<$Text::Wrap::tabstop> to +the number of characters you do want for your tabstops. + +If you want to separate your lines with something other than C<\n> +then set C<$Text::Wrap::seporator> to your preference. + +When words that are longer than C<$columns> are encountered, they +are broken up. C<wrap()> adds a C<"\n"> at column C<$columns>. +This behavior can be overridden by setting C<$huge> to +'die' or to 'overflow'. When set to 'die', large words will cause +C<die()> to be called. When set to 'overflow', large words will be +left intact. + +Historical notes: 'die' used to be the default value of +C<$huge>. Now, 'wrap' is the default value. + +=head1 EXAMPLE + + print wrap("\t","","This is a bit of text that forms + a normal book-style paragraph"); + +=head1 AUTHOR + +David Muir Sharnoff <muir@idiom.com> with help from Tim Pierce and +many many others. + |