Resolve "Feature: Send endpoint for attributes"

Closes #38 (closed)

pages/docs/dsl.md

@@ -13,7 +13,7 @@ The kind of the element determines, whether an endpoint for it can be receiving,
 To declare a new endpoints, use the following syntax:
 
 ```
-("send"|"receive") ["indexed"] ["with add"] <Non-Terminal>[.<Target>["()"]] ["using" <Mapping-Name> (, <Mapping-Name>)*] ";"
+("send"|"receive") ["indexed"] ["with add"] <Non-Terminal>[.<Target>["(<AttributeType>)"]] ["using" <Mapping-Name> (, <Mapping-Name>)*] ";"
 ```
 
 A breakdown of the parts of that syntax:
@@ -28,10 +28,12 @@ A breakdown of the parts of that syntax:
 - The second optional keyword `with add` can also be used only for receiving endpoints targeting a list children.
   As described above, it can be combined with `indexed`.
   If used on its own, the incoming data is interpreted as a complete list and its elements will be appended to the current list.
-- The `<Non-Terminal>[.<Target>["()"]]` notation describes the actual affected node.
+- The `<Non-Terminal>[.<Target>["(<AttributeType>)"]]` notation describes the actual affected node.
   - If the target is omitted, all nodes of that non-terminal type can be connected, irrespective of their context. This is a context-free endpoint definition.
   - The target can be any child on the right-hand side of a production rule, a role of a relation, or an attribute.
-    The brackets `()` after the target must be used in case of an attribute, and only then.
+    The brackets `(<AttributeType>)` after the target must be used in case of an attribute, and only then.
+    Here, the return type of the attribute has to be specified, as aspect files are not parsed by RagConnect.
+    Hence, RagConnect can not and will not verify the existence of the attribute, and the possible non-existence of an attribute will be found by the Java compiler.
 - Optionally, an endpoint can use one or more [mappings](#mappings).
   They will be applied before sending, or after receiving a message.
   Mappings will always be applied in the order they are listed after `using`.