PsiTag supports append, delete, and strict modes now

content can appear multiline if scope is block

block is between ( ) multiline

tagging and mode must appear in the same line

automatic tagging is possible with .= content

Mode is either

             add definition and overwrite if it exits =

             add definition and append to it if it exits +=

             add definition or ignore if it exits =?

             add definition or fail if it exits =!

             delete definition or ignore if it doesn't exist -=

             delete definition or fail if it exits -=!

             delete from definition or ignore if it doesn't exist -=

             delete from definition or fail if it exits -=!

tagging must not contain any of = + ? ! - < & *

Content is subject to interpretation as follows.

   (0) sometag = ()

	Deletes sometag if it exits. Spaces around =  are optional. Note that

       sometag =

       sets the content of sometag to nothing, and is different from deletion.

   (1) First non-whitespace character after mode in the same line, if it is a (

   (2) Last non-whitespace character in a line, if it is a )

		}

		if (!$blockScope) {

			next if ($line =~ /^\#/ or isEmptyLine($line));

			if ($line =~ /^([^\=\+\?\!\-\<\&\*]+)([\=\+\?\!\-\<\&\*][^ \t]*)(.*)$/) {

			if ($line =~ /^([^\=\+\?\!\-\<\&\*]+)\=[ \t]*\(\)[ \t]*$/) {

				my $tag = $1;

				removeTag($tags, canonicalTagName($tag));

				next;

			}

			if ($line =~ /^([^\=\+\?\!\-\<\&\*]+)([\=\+\?\!\-\<\&\*]+)[ \t]*(.*)$/) {

				my $tag = $1;

				my $mode = $2;

				my $rest = $3;

					syntaxError($line, $i + 1);

				}

				($tag) or die "$0: tag does not exist in line scope $line\n";

				($tag) or die "$0: FATAL: tag does not exist in line scope $line\n";

				if ($thisLineParens > 0) {

					$blockScope = 1;

					$multilineContent = "";

sub addTag

{

	my ($tags, $tag, $mode, $content) = @_;

	#print STDERR "$0: Adding $tag, ignoring $mode\n";

	$tags->{"$tag"} = {"content" => $content};

	# mode is 

	# = (add or overwrite) 

	# += (append) 

	# -= (delete) 

	# =? (selective add)

	# =! (strict add)

	# -=! (strict delete)

	# Does the tag exist?

	my $mytag = $tags->{"$tag"};

	my $b = defined($mytag);

	my $oldContent = ($b) ? $tags->{"$tag"}{"content"} : "";

	my $append = (($mode eq "=?" && !$b) or ($mode eq "+=") or ($mode eq "=!" && !$b) or ($mode eq "="));

	die "$0: FATAL: Adding tag $tag with $mode, but $tag already exists\n" if ($mode eq "=!" && $b);

	return if ($mode eq "=?" && $b);

	if ($append) {

		$oldContent = "" if ($mode eq "=");

		$tags->{"$tag"} = {"content" => "$oldContent$content"};

		return;

	}

	if ($mode eq "-=" or $mode eq "-=!") {

		print STDERR "$0: WARNING: Deletion of content in non-existing tag $tag\n" if (!$b);

		my $hasIt = ($oldContent =~ /\Q$content/);

		die "$0: FATAL: Strict delete of non-existing content in tag $tag\n" if ($mode eq "-=!" && !$hasIt);

		return if (!$hasIt);

		$oldContent =~ s/\Q$content//g if ($hasIt);

		$tags->{"$tag"} = {"content" => "$oldContent"};

		return;

	}

	die "$0: FATAL: Unknown mode $mode applied to tag $tag\n";	

}

sub removeTag

{

	my ($tags, $tag) = @_;

	defined($tags->{"$tag"}) or return;	

	delete $tags->{"$tag"};

}

sub syntaxError

{

	my ($line, $ind) = @_;

	print STDERR "$0: Syntax error line $ind\n";

	print STDERR "$0: FATAL: Syntax error line $ind\n";

	die "$0: ----> $line <------\n";

}

		my $content = $line;

		if ($line =~ /^[ \t]*\<(.*$)/) { # (3) in block scope

			my $existingTag = $1;

			($existingTag) or die "$0: Tag does not exist in unWrap: $line\n";

			($existingTag) or die "$0: FATAL: Tag does not exist in unWrap: $line\n";

			$existingTag = canonicalTagName($existingTag);

			my $ptr = $tags->{"$existingTag"};

			defined($ptr) or die "$0: Tag $existingTag doesn't exist\n";

			(ref($ptr) eq "HASH") or die "$0: Tag $existingTag not hash ref but ".ref($ptr)."\n";

			defined($ptr) or die "$0: FATAL: Tag $existingTag doesn't exist\n";

			(ref($ptr) eq "HASH") or die "$0: FATAL: Tag $existingTag not hash ref but ".ref($ptr)."\n";

			$content = $ptr->{"content"};

			defined($content) or die "$0: No content for $existingTag\n";

			defined($content) or die "$0: FATAL: No content for $existingTag\n";

			$content = unWrap($tags, $content);

		}