Automatic generation produced by ISE Eiffel
deferred class OBJECT_GRAPH_TRAVERSABLE General cluster: elks description: "Utility class to traverse object graphs starting at a root object. When traversing a graph the class distinguishes four different types of references: (1) Normal references (2) References with copy-semantics, which are usually seen when attaching an expanded object to an ANY reference (3) User-defined expanded objects, embedded inside another object. Semantically this is a special case of a copy-semantics reference. (4) Language-defined expanded objects (INTEGER, POINTER etc) embedded inside another object. Semantically, this is a special case of a copy-semantics reference. This class will follow all reference types except (4). During traversal the agent on_processing_object_action will be called for each object and the agent on_processing_reference_action for each reference, if present. This includes references to objects that have already been processed. The algorighm has two output values: visited_objects and visited_types: Any standard object without copy-semantics (i.e. reference type (1)) will be stored by aliasing inside visited_object. For references of type (2) and (3) a copy will be stored. The visited_types hash table contains the dynamic type id of all types encountered during traversal. The key and value in the hashtable are the same. Setting is_skip_copy_semantics_reference to true means that references of (2) and (3) will not be stored in visited_types. Note that this is the only effect of this setting - i.e. the traversal algorithm will still follow the references, the agents will be called, and the visited_types array will be extended anyway. NOTE: Due to a limitation in the reflection library, references of type (2) and (3) within TUPLE and references of type (3) within SPECIAL cannot be handled without causing a copy. This is problematic for agents, especially when they want to change the object. Therefore the algorithm will raise an exception when an agent is attached. In read-only situations it may be acceptable to use a copy of an object. Therefore to disable the exception behaviour you can set is_exception_on_copy_suppressed to True. NOTE: To maintain backwards compatibility the traversal algorithm will silently ignore any kind of exception and just return normally, with traversed_objects set to whatever value it had before invoking traverse. In order to get exceptions you need to set is_exception_propagated to True." Ancestors ANY Queries has_failed: BOOLEAN has_reference_with_copy_semantics: BOOLEAN is_exception_on_copy_suppressed: BOOLEAN is_exception_propagated: BOOLEAN is_object_action_set: BOOLEAN is_root_object_set: BOOLEAN is_skip_copy_semantics_reference: BOOLEAN is_skip_transient: BOOLEAN object_action: detachable PROCEDURE [separate ANY] on_processing_object_action: detachable PROCEDURE [REFLECTED_OBJECT] on_processing_reference_action: detachable PROCEDURE [REFLECTED_OBJECT, REFLECTED_OBJECT] root_object: detachable ANY visited_objects: detachable ARRAYED_LIST [separate ANY] visited_types: detachable HASH_TABLE [INTEGER_32, INTEGER_32] Commands set_is_exception_on_copy_suppressed (v: [like is_exception_on_copy_suppressed] BOOLEAN) set_is_exception_propagated (v: [like is_exception_propagated] BOOLEAN) set_is_skip_copy_semantics_reference (v: [like is_skip_copy_semantics_reference] BOOLEAN) set_is_skip_transient (v: [like is_skip_transient] BOOLEAN) set_on_processing_object_action (an_action: [like on_processing_object_action] detachable PROCEDURE [REFLECTED_OBJECT]) set_on_processing_reference_action (an_action: [like on_processing_reference_action] detachable PROCEDURE [REFLECTED_OBJECT, REFLECTED_OBJECT]) set_root_object (an_object: [like root_object] detachable ANY) traverse wipe_out -- Generated by Eiffel Studio --
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