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can_a_role_be_played_by_several_different_objects_in_a_given_context_instantiation

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can_a_role_be_played_by_several_different_objects_in_a_given_context_instantiation [2014/01/20 01:56]
gazoot created
can_a_role_be_played_by_several_different_objects_in_a_given_context_instantiation [2014/03/11 13:35] (current)
gazoot Added a more technical explanation.
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 No. All Roles are bound as an atomic operation before an Interaction starts. And the Role being an alias for a single object, means that there can only be one object per Role during an Interaction. ​ No. All Roles are bound as an atomic operation before an Interaction starts. And the Role being an alias for a single object, means that there can only be one object per Role during an Interaction. ​
  
-Why is switching a problem? Imagine switching your favorite James Bond actor for your least favorite //during the same movie//.+Why is switching ​(rebinding during Interaction) ​a problem? ​It creates a conflict with the mental model. Objects in a certain context must be the same as they were at all points during an Interaction. If you write a Use Case for example, any object referred to in the beginning must be the same at the end, for consistency reasons. The same goes for Contexts (and a goal with DCI is to map Use Cases to code.) 
 + 
 +A somewhat halting analogy of the above confusion: ​Imagine switching your favorite James Bond actor for your least favorite //during the same movie//.
  
 Note: The Roles can all be rebound before another Interaction in the same Context occurs. Note: The Roles can all be rebound before another Interaction in the same Context occurs.
can_a_role_be_played_by_several_different_objects_in_a_given_context_instantiation.1390183002.txt.gz · Last modified: 2014/01/20 01:56 by gazoot