anchor.diff:  ----
   
   is permitted because the number of parameters differs.
  +
  +=== Asynchronous operations
  +
  +Asynchronous operations can be declared using method with callback or method returning futures.
  +
  +The default mode declares asynchronous operations with a method having a trailing callback, e.g
  +
  +[source,java]
  +----
  +// A callback methods that declares an synchronous operation yielding to a buffer or a failure
  +void getValue(Handler<AsyncResult<Buffer>> handler);
  +----
  +
  +Callback methods can have a future companion method with a future returning signature:
  +
  +[source,java]
  +----
  +Future<Buffer> getValue();
  +----
  +
  +Such method is ignored by codegen because it represents the same asynchronous operation declared by the handler above.
  +
  +This specific schemes was developed with backward compatibility of Vert.x 3 and Vert.x modules that were developed
  +in Vert.x 3 and still available in Vert.x 4 use it.
  +
  +New Vert.x modules developed exclusively for Vert.x 4 can declare methods with only future returning signatures.
  +
  +The module needs to be declared accordingly:
  +
  +[source,java]
  +----
  +@ModuleGen(name = "acme", groupPackage="com.acme", useFutures = true)
  +package com.acme.myservice;
  +
  +import io.vertx.codegen.annotations.ModuleGen;
  +----
  +
  +Then asynchronous operation only need to return a Vert.x future.
   
   === Static methods
   
  
positive.code: . a `java.util.List<V>`, `java.util.Set<V>` or `java.util.Map<String, V>` where `<V>` can be a _basic_ type,
  a _json_ type. For list and set `V` can also be an _API_ type, an _enum_ type or a _data object_ type
  
  Function parameters are allowed, i.e types declaring `java.util.function.Function<E, R>` where `<E>` is defined to
  be same than for handlers and `<R>` can be:
  
  
negative.code: 
  === Modules
  
  A module contains a collection of Vert.x API and data objects declarations., some shim uses modules for organizing
  and loading the Vert.x api:
  
  - the JavaScript shim uses https://en.wikipedia.org/wiki/CommonJS[CommonJS] modules
  