{"record":{"id":"21dfcdfdcf2992e2","repo":"rohitg00/ai-engineering-from-scratch","slug":"slice-read-produced-cursor-tokens-expected-sto","errorCode":null,"errorMessage":"slice read produced {cursor} tokens, expected {stop - start}","messagePattern":"slice read produced (.+?) tokens, expected (.+?)","errorType":"exception","errorClass":"RuntimeError","httpStatus":null,"severity":"error","filePath":"phases/19-capstone-projects/43-hdf5-tokenized-corpus/code/main.py","lineNumber":327,"sourceCode":"            return np.empty((0,), dtype=TOKEN_DTYPE)\n        out = np.empty((stop - start,), dtype=TOKEN_DTYPE)\n        cursor = 0\n        for entry, dataset in zip(self._entries, self._datasets):\n            shard_start = entry.global_start\n            shard_stop = shard_start + entry.token_count\n            if stop <= shard_start:\n                break\n            if start >= shard_stop:\n                continue\n            local_start = max(0, start - shard_start)\n            local_stop = min(entry.token_count, stop - shard_start)\n            length = local_stop - local_start\n            if length <= 0:\n                continue\n            out[cursor : cursor + length] = dataset[local_start:local_stop]\n            cursor += length\n        if cursor != stop - start:\n            raise RuntimeError(\n                f\"slice read produced {cursor} tokens, expected {stop - start}\"\n            )\n        return out\n\n\nclass SlidingWindowDataloader:\n    \"\"\"Random sliding-window sampler over a flat token stream.\"\"\"\n\n    def __init__(\n        self,\n        store: MmapTokenStore,\n        window_size: int = DEFAULT_WINDOW_SIZE,\n        batch_size: int = 4,\n        seed: int = 0,\n    ) -> None:\n        if window_size <= 1:\n            raise ValueError(\"window_size must be greater than 1\")\n        if batch_size <= 0:","sourceCodeStart":309,"sourceCodeEnd":345,"githubUrl":"https://github.com/rohitg00/ai-engineering-from-scratch/blob/39ea8a1c6d0b61f071226eff7ede4d4105fed820/phases/19-capstone-projects/43-hdf5-tokenized-corpus/code/main.py#L309-L345","documentation":"Error \"slice read produced {cursor} tokens, expected {stop - start}\" thrown in rohitg00/ai-engineering-from-scratch.","triggerScenarios":"Thrown at phases/19-capstone-projects/43-hdf5-tokenized-corpus/code/main.py:327 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"39ea8a1c6d0b61f071226eff7ede4d4105fed820","analyzedAt":"2026-08-26T03:13:46.626Z","schemaVersion":2},"datasetVersion":"2026-08-26T07:17:17.940Z"}