Data::Sofu::Undefined - A Sofu non type

Provides a interface similar to the original SofuD (sofu.sf.net)

This Object is similar to Perl's undef .

It is nothing (not even a Data::Sofu::Value) but it is still there (in Lists or Maps for example)

	require Data::Sofu::Undefined;
	require Data::Sofu::Map;
	my $u = Data::Sofu::Undefined->new();
	my $map = Data::Sofu::Map->new();
	$map->setAttribute("Nx",$u);
	$map->hasMap("Nx"); # Returns 0
	$map->hasValue("Nx"); # Returns 0
	$map->hasAttribute("Nx"); # Returns 1
	# It is also there in $map->each() and $map->next();	

This Module is pure OO, exports nothing

Also look at Data::Sofu::Object for methods, cause Undefined inherits from it

Creates a new Data::Sofu::Undefined and returns it

	$val = Data::Sofu::Undefined->new();

Returns false

Returns the string representation of this Object.

Which is the string "UNDEF"

LEVEL and TREE are ignored.

Returns a binary representation of this Object. Don't call this (will be called from packBinary() and writeBinary())

This still tests true when using:

	my $u=Data::Sofu::Undefined->new();
	if ($u) { 
		#This will happen.
	}
	if ($u->isDefined()) { 
		#This will not happen.
	}

Data::Sofu, Data::Sofu::Value, Data::Sofu::Object, Data::Sofu::Map, Data::Sofu::Value, Data::Sofu::Reference, http://sofu.sf.net