X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FText%2FTabs.pm;h=610e870c11fb2eff24066073243db25cb67eb898;hb=fe0438b3fdd7184c1a19b7c24a3a26460d03083a;hp=c90d1aa672e538e0c3279bd335297c1081f4f380;hpb=75f926282bd78abe2f394977be7dd4dc52cb21ba;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/Text/Tabs.pm b/lib/Text/Tabs.pm
index c90d1aa..610e870 100644
--- a/lib/Text/Tabs.pm
+++ b/lib/Text/Tabs.pm
@@ -1,12 +1,3 @@
-#
-# expand and unexpand tabs as per the unix expand and 
-# unexpand programs.
-#
-# expand and unexpand operate on arrays of lines.  Do not
-# feed strings that contain newlines to them.
-#
-# David Muir Sharnoff <muir@idiom.com>
-# 
 
 package Text::Tabs;
 
@@ -15,33 +6,131 @@ require Exporter;
 @ISA = (Exporter);
 @EXPORT = qw(expand unexpand $tabstop);
 
-$tabstop = 8;
+use vars qw($VERSION $tabstop $debug);
+$VERSION = 2007.1117;
 
-sub expand
-{
-	my @l = @_;
-	for $_ (@l) {
-		1 while s/^([^\t]*)(\t+)/
-			$1 . (" " x 
-				($tabstop * length($2)
-				- (length($1) % $tabstop)))
-			/e;
+use strict;
+
+BEGIN	{
+	$tabstop = 8;
+	$debug = 0;
+}
+
+sub expand {
+	my @l;
+	my $pad;
+	for ( @_ ) {
+		my $s = '';
+		for (split(/^/m, $_, -1)) {
+			my $offs = 0;
+			s{\t}{
+				$pad = $tabstop - (pos() + $offs) % $tabstop;
+				$offs += $pad - 1;
+				" " x $pad;
+			}eg;
+			$s .= $_;
+		}
+		push(@l, $s);
 	}
-	return @l;
+	return @l if wantarray;
+	return $l[0];
 }
 
 sub unexpand
 {
-	my @l = &expand(@_);
+	my (@l) = @_;
 	my @e;
+	my $x;
+	my $line;
+	my @lines;
+	my $lastbit;
+	my $ts_as_space = " "x$tabstop;
 	for $x (@l) {
-		@e = split(/(.{$tabstop})/,$x);
-		for $_ (@e) {
-			s/  +$/\t/;
+		@lines = split("\n", $x, -1);
+		for $line (@lines) {
+			$line = expand($line);
+			@e = split(/(.{$tabstop})/,$line,-1);
+			$lastbit = pop(@e);
+			$lastbit = '' 
+				unless defined $lastbit;
+			$lastbit = "\t"
+				if $lastbit eq $ts_as_space;
+			for $_ (@e) {
+				if ($debug) {
+					my $x = $_;
+					$x =~ s/\t/^I\t/gs;
+					print "sub on '$x'\n";
+				}
+				s/  +$/\t/;
+			}
+			$line = join('',@e, $lastbit);
 		}
-		$x = join('',@e);
+		$x = join("\n", @lines);
 	}
-	return @l;
+	return @l if wantarray;
+	return $l[0];
 }
 
 1;
+__END__
+
+sub expand
+{
+	my (@l) = @_;
+	for $_ (@l) {
+		1 while s/(^|\n)([^\t\n]*)(\t+)/
+			$1. $2 . (" " x 
+				($tabstop * length($3)
+				- (length($2) % $tabstop)))
+			/sex;
+	}
+	return @l if wantarray;
+	return $l[0];
+}
+
+
+=head1 NAME
+
+Text::Tabs -- expand and unexpand tabs per the unix expand(1) and unexpand(1)
+
+=head1 SYNOPSIS
+
+  use Text::Tabs;
+
+  $tabstop = 4;  # default = 8
+  @lines_without_tabs = expand(@lines_with_tabs);
+  @lines_with_tabs = unexpand(@lines_without_tabs);
+
+=head1 DESCRIPTION
+
+Text::Tabs does about what the unix utilities expand(1) and unexpand(1) 
+do.  Given a line with tabs in it, expand will replace the tabs with
+the appropriate number of spaces.  Given a line with or without tabs in
+it, unexpand will add tabs when it can save bytes by doing so (just
+like C<unexpand -a>).  Invisible compression with plain ASCII! 
+
+=head1 EXAMPLE
+
+  #!perl
+  # unexpand -a
+  use Text::Tabs;
+
+  while (<>) {
+    print unexpand $_;
+  }
+
+Instead of the C<expand> comand, use:
+
+  perl -MText::Tabs -n -e 'print expand $_'
+
+Instead of the C<unexpand -a> command, use:
+
+  perl -MText::Tabs -n -e 'print unexpand $_'
+
+=head1 LICENSE
+
+Copyright (C) 1996-2002,2005,2006 David Muir Sharnoff.  
+Copyright (C) 2005 Aristotle Pagaltzis 
+This module may be modified, used, copied, and redistributed at your own risk.
+Publicly redistributed modified versions must use a different name.
+