code: public static <T> T operator_doubleArrow(T object, Procedure1<? super T> block) {
  		block.apply(object);
  		return object;
  	}
docs: The <code>doubleArrow</code> operator is used as a 'with'- or 'let'-operation.
  It allows to bind an object to a local scope in order to do something on it.
  
  Example:
  <code>
  new Person => [
  firstName = 'Han'
  lastName = 'Solo'
  ]
  </code>
  
  @param object
  an object. Can be <code>null</code>.
  @param block
  the block to execute with the given object. Must not be <code>null</code>.
  @return the reference to object.
  @since 2.3