Adds documentation on how to build classes

Using the metamodel. Closes #1641

Author: JJ

doc/Type/Metamodel/ClassHOW.pod6

@@ -101,7 +101,7 @@ It is potentially faster than C<.^can> but does not provide a full list of all c
 
 =head2 method compose
 
-    method compose(Metamodel::ClassHOW:D: $obj)
+      method compose(Metamodel::ClassHOW:D: $obj)
 
 A call to C<compose> brings the meta object and thus the class it represents
 into a fully functional state, so if you construct or modify a class, you must
@@ -111,4 +111,21 @@ It updates the method cache, checks that all methods that are required by
 roles are implemented, does the actual role composition work, and sets up
 the class to work well with language interoperability.
 
+=head2 method new_type
+
+    method (:$name, :$repr = 'P6opaque', :$ver, :$auth)
+
+Creates a new type from the metamodel, which we can proceed to build
+
+    my $type = Metamodel::ClassHOW.new_type(name => "NewType",
+                                            ver => v0.0.1,
+                                            auth => 'github:perl6' );
+    $type.HOW.add_method($type,"hey", method { say "Hey" });
+    $type.hey;     # OUTPUT: «Hey␤»
+    $type.HOW.compose($type);
+    my $instance = $type.new;
+    $instance.hey; # OUTPUT: «Hey␤»
+
+We add a single method by using L<Higher Order Workings|/language/mop#index-entry-syntax_HOW-HOW> methods, and then we can use that method directly as class method; we can then C<compose> the type, following which we can create already an instance, which will behave in the exact same way.
+
 =end pod

xt/words.pws

@@ -1375,3 +1375,4 @@ zoffixznet
 zwj
 mmk
 FQN
+NewType