Example for categorize refs #1731

doc/Type/Any.pod6

@@ -860,17 +860,39 @@ say %leap-years
 # => [2002-01-01 2003-01-01 2005-01-01 2006-01-01 2007-01-01 2009-01-01],
 #    True => [2004-01-01 2008-01-01]}␤»
 
+The function used to categorize can return an array indicating all possible bins
+their argument can be put into:
+
+=begin code
+sub divisible-by( Int $n --> Array(Seq) ) {
+    gather {
+        for <2 3 5 7> {
+            take $_ if $n %% $_;
+        }
+    }
+}
+
+say (3..13).categorize( &divisible-by );
+# OUTPUT:
+# «{2 => [4 6 8 10 12], 3 => [3 6 9 12], 5 => [5 10], 7 => [7]}␤»
+=end code
+
+In this case, every number in the range is classified in as many bins as it can
+be divided by.
+
 =head2 method classify
 
 Defined as:
 
-    method classify(&mapper -->Hash:D)
+    multi method classify()
+    multi method classify(Whatever)
+    multi method classify($test, :$into!, :&as)
+    multi method classify($test, :&as)
+    multi sub classify($test, +items, :$into!, *%named )
+    multi sub classify($test, +items, *%named )
 
-Coerces the invocant to a C<list> by applying
-its L«C<.list>|/routine/list» method and uses
-L«C<List.classify>|/type/List#routine_classify» on it.
+The two first forms will fail.
 
-    say Any.classify({ $_ }); # OUTPUT: «{(Any) => [(Any)]}␤»
 
 =head2 method produce