Add support for :skip-null

META.info

@@ -2,7 +2,7 @@
    "provides" : {
       "JSON::Class" : "lib/JSON/Class.pm"
    },
-   "version" : "0.0.3",
+   "version" : "0.0.4",
    "test-depends" : [
       "Test"
    ],

README.md

@@ -33,6 +33,14 @@ both serialisation and de-serialisation.  The exact behaviour depends on that
 of (JSON::Marshal)[https://github.com/jonathanstowe/JSON-Marshal] and
 (JSON::Unmarshal)[https://github.com/tadzik/JSON-Unmarshal] respectively.
 
+
+If the ```:skip-null``` adverb is provided to ```to-json``` all attributes
+without a defined value will be ignored in serialisation. If you need
+finer grained control then you should apply the ```json-skip-null```
+attribute trait (defined by ```JSON::Marshal``` ) to the traits you
+want to skip if they aren't defined (```:json-skip``` will still have
+the same effect though.)
+
 The  (JSON::Marshal)[https://github.com/jonathanstowe/JSON-Marshal] and
 (JSON::Unmarshal)[https://github.com/tadzik/JSON-Unmarshal] provide traits
 for controlling the unmarshalling/marshalling of specific attributes which are

lib/JSON/Class.pm

@@ -58,12 +58,19 @@ type for the target class then an exception may be thrown.
 
 =head2 method to-json
 
-    method to-json() returns Str
+    method to-json(Bool :$skip-null) returns Str
 
 Serialises the public attributes of the object to a JSON string that
 represents the object, this JSON can be fed to the L<from-json> of the
 class to create a new object with matching (public) attributes.
 
+If the C<:skip-null> adverb is provided all attributes without a
+defined value will be ignored in serialisation. If you need finer
+grained control then you should apply the C<json-skip-null> attribute
+trait (defined by L<JSON::Marshal> ) to the traits you want to skip
+if they aren't defined (C<:json-skip> will still have the same effect
+though.)
+
 =end pod
 
 use JSON::Unmarshal;
@@ -73,15 +80,15 @@ sub EXPORT {
     { '&trait_mod:<is>'    =>  &trait_mod:<is> }
 }
 
-role JSON::Class:ver<0.0.3>:auth<github:jonathanstowe> {
+role JSON::Class:ver<0.0.4>:auth<github:jonathanstowe> {
 
 
     method from-json(Str $json) returns JSON::Class {
         unmarshal($json, self);
     }
 
-    method to-json() returns Str {
-        marshal(self);
+    method to-json(Bool :$skip-null) returns Str {
+        marshal(self, :$skip-null);
     }
 }