{"record":{"id":"71ca8504c9fffaaf","repo":"microsoft/qlib","slug":"subclass-of-calendarstorage-must-implement-deli","errorCode":null,"errorMessage":"Subclass of CalendarStorage must implement `__delitem__(i: int)`/`__delitem__(s: slice)`  method","messagePattern":"Subclass of CalendarStorage must implement `__delitem__\\(i: int\\)`/`__delitem__\\(s: slice\\)`  method","errorType":"exception","errorClass":"NotImplementedError","httpStatus":null,"severity":"error","filePath":"qlib/data/storage/storage.py","lineNumber":154,"sourceCode":"            \"Subclass of CalendarStorage must implement `__setitem__(i: int, o: CalVT)`/`__setitem__(s: slice, o: Iterable[CalVT])`  method\"\n        )\n\n    @overload\n    def __delitem__(self, i: int) -> None:\n        \"\"\"x.__delitem__(i) <==> del x[i]\"\"\"\n\n    @overload\n    def __delitem__(self, i: slice) -> None:\n        \"\"\"x.__delitem__(slice(start: int, stop: int, step: int)) <==> del x[start:stop:step]\"\"\"\n\n    def __delitem__(self, i) -> None:\n        \"\"\"\n        Raises\n        ------\n        ValueError\n            If the data(storage) does not exist, raise ValueError\n        \"\"\"\n        raise NotImplementedError(\n            \"Subclass of CalendarStorage must implement `__delitem__(i: int)`/`__delitem__(s: slice)`  method\"\n        )\n\n    @overload\n    def __getitem__(self, s: slice) -> Iterable[CalVT]:\n        \"\"\"x.__getitem__(slice(start: int, stop: int, step: int)) <==> x[start:stop:step]\"\"\"\n\n    @overload\n    def __getitem__(self, i: int) -> CalVT:\n        \"\"\"x.__getitem__(i) <==> x[i]\"\"\"\n\n    def __getitem__(self, i) -> CalVT:\n        \"\"\"\n\n        Raises\n        ------\n        ValueError\n            If the data(storage) does not exist, raise ValueError","sourceCodeStart":136,"sourceCodeEnd":172,"githubUrl":"https://github.com/microsoft/qlib/blob/79633dd9506ea689e5400dea0197717b5b3d74b7/qlib/data/storage/storage.py#L136-L172","documentation":"Error \"Subclass of CalendarStorage must implement `__delitem__(i: int)`/`__delitem__(s: slice)`  method\" thrown in microsoft/qlib.","triggerScenarios":"This error is raised at qlib/data/storage/storage.py:154 when the guard condition fails: \"Subclass of CalendarStorage must implement `__delitem__` method\". It triggers when the code path receives input or a state that violates the precondition checked at this point — e.g. an unimplemented abstract method being called, an unsupported argument type/value, or an invalid configuration. To avoid it, satisfy the documented precondition before this call: implement the required method in your subclass, or pass a supported value of the expected type as described by the message.","commonSituations":"See trigger scenarios.","solutions":["Implement `__delitem__` (both int and slice forms) in your CalendarStorage subclass.","Use the built-in FileCalendarStorage which implements `__delitem__`."],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"79633dd9506ea689e5400dea0197717b5b3d74b7","analyzedAt":"2026-08-15T07:01:27.511Z","schemaVersion":2},"datasetVersion":"2026-08-15T22:17:37.221Z"}