my @lines = (
	"@attribute 'Sex' { Male, Female}",
	"@attribute 'Feature 0' real",
	"@attribute 'Feature 1' real",
	"@attribute 'Feature 2' real",
	"@attribute Malic_acid REAL",
	"@attribute Ash REAL"
	);
foreach my $line (@lines) {
	$line =~ /^@attribute\s+[']?(.*?)[']?\s+[{]?(.*?)[}]?$/;
	print "relation name: $1\n";
	print "type: $2\n";
}

##</code><code>##

perl test.pl
relation name: Sex
type:  Male, Female
relation name: Feature
type: 0' real
relation name: Feature
type: 1' real
relation name: Feature
type: 2' real
relation name: Malic_acid
type: REAL
relation name: Ash
type: REAL