MOP: can, parents

Author: moritz

lib/objects.pod

@@ -468,6 +468,24 @@ Introspection is the process of getting information about an object or class
 at runtime. In Perl 6, all introspection goes through the meta object. The
 standard C<ClassHOW> for class-based objects offers these facilities:
 
+=head3 can
+
+Given a method names, it returns a L<Parcel> of methods that are available
+with this name.
+
+    class A      { method x($a) {} };
+    class B is A { method x()   {} };
+    say B.^can('x').elems;              # 2
+    for B.^can('x') {
+        say .arity;                     # 1, 2
+    }
+
+In this example, class C<B> has two possible methods available with name C<x>
+(though a normal method call would only invoke the one installed in C<B>
+directly). The one in C<B> has arity 1 (i.e. it expects one argument, the
+invocant (C<self>)), and the one in C<A> expects 2 arguments (C<self> and
+C<$a>).
+
 =head3 methods
 
 Returns a list of public methods available on the class (which includes
@@ -497,4 +515,20 @@ Returns the name of the class:
 
     say 'a string'.^name;               # Str
 
+=head3 parents
+
+Returns the list of parent classes. By default it stops at L<Cool>, L<Any> or
+L<Mu>, which you can suppress by supplying the C<:all> adverb. With C<:tree>,
+a nested list is returned.
+
+    class D { };
+    class C1 is D { };
+    class C2 is D { };
+    class B is C1 is C2 { };
+    class A is B { };
+
+    say A.^parents(:all).perl;          # (B, C1, C2, D, Any, Mu)
+    say A.^parents(:all, :tree).perl;
+        # ([B, [C1, [D, [Any, [Mu]]]], [C2, [D, [Any, [Mu]]]]],)
+
 =end pod