show namespaces for identifiers

doc/Language/syntax.pod6

@@ -178,6 +178,13 @@ Names of constants, types (including classes and modules) and routines (subs
 and methods) are identifiers, and they also appear in variable names (usually
 proceeded by a sigil; see L<variables|/language/variables> for more details.)
 
+Namespaces are provided by L<packages|/language/packages>. By separating
+identifiers with double colons, the right most name is inserted into existing
+or automatically created packages.
+
+    my Int $Foo::Bar::buzz = 42;
+    dd $Foo::Bar::buzz; # OUTPUT«Int $v = 42␤»
+
 =head1 Statements and Expressions
 
 Perl 6 programs are made of lists of statements. A special case of a statement