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   # information regarding copyright ownership.
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Requirements
############

.. document:: Result Library Requirements
   :id: doc__result_lib_requirements
   :status: draft
   :safety: ASIL_B
   :realizes: wp__requirements_comp
   :tags: requirements, result_library

Functional Requirements
=======================

.. comp_req:: Result-Based Error Handling
   :id: comp_req__result__error_handling
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__core_utilities, feat_req__baselibs__result_library, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall provide an error handling mechanism that enables functions to return either successful values or error information without using C++ exceptions.

.. comp_req:: Domain-Specific Error Information
   :id: comp_req__result__domain_error_information
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__core_utilities, feat_req__baselibs__result_library, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall support user-defined error domains and error codes.

.. comp_req:: Type-Safe Error Handling
   :id: comp_req__result__type_safety
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__consistent_apis, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall enforce compile-time type safety for error handling operations.

.. comp_req:: Standard Library Integration
   :id: comp_req__result__std_integration
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__consistent_apis, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall provide conversion utilities to transform Result objects into standard library optional type, with enforced error handling.

Non-Functional Requirements
===========================

.. comp_req:: Deterministic Behavior
   :id: comp_req__result__deterministic_behavior
   :reqtype: Non-Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__core_utilities, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall provide deterministic behavior with no dynamic memory allocation.

.. comp_req:: Exception-Free Operation
   :id: comp_req__result__exception_free_operation
   :reqtype: Non-Functional
   :security: NO
   :safety: ASIL_B
   :satisfies: feat_req__baselibs__core_utilities, feat_req__baselibs__safety
   :status: valid
   :tags: inspected

   The Result library shall operate without throwing C++ exceptions.

Assumptions of Use (AoU)
========================

.. aou_req:: Error Domain Implementation
   :id: aou_req__result__error_domain_implementation
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :status: valid
   :tags: inspected

   The user shall implement error domain classes and error code enumerations according to the library's interface specification.

.. aou_req:: Result Value Handling
   :id: aou_req__result__value_handling
   :reqtype: Functional
   :security: NO
   :safety: ASIL_B
   :status: valid
   :tags: inspected

   The user shall check and handle both successful and error states of Result objects before accessing contained values to prevent undefined behavior.

.. aou_req:: Thread Safety
   :id: aou_req__result__thread_safety
   :reqtype: Non-Functional
   :security: NO
   :safety: ASIL_B
   :status: valid
   :tags: inspected

   The user shall ensure appropriate synchronization mechanisms when using Result objects in multi-threaded environments, as the library provides no internal thread safety guarantees.

.. aou_req:: Resource Lifetime
   :id: aou_req__result__resource_lifetime
   :reqtype: Non-Functional
   :security: NO
   :safety: ASIL_B
   :status: valid
   :tags: inspected

   The user shall ensure that error domain objects and referenced resources remain valid throughout the entire lifetime of any dependent Result or Error objects.


.. needextend:: "__result__" in id
   :+tags: baselibs
.. needextend:: "result" in id
   :+tags: result_library