Details
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Bug
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Status: Resolved
-
Major
-
Resolution: Fixed
-
0.2.0
-
None
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Linux
Description
arrow::io::ReadWriteFileInterface inheritances arrow::io::FileInterface
as diamond style via:
- ReadableFileInterface -> InputStream -> FileInterface
- WriteableFileInterface -> OutputStream -> FileInterface
If we have diamond inheritance, we can't cast subclasses of
arrow::io::ReadWriteFileInterface such as arrow::io::MemoryMappedFile to
arrow::io::FileInterface.
C++:
#include <arrow/io/file.h>
int
main(void)
Build result:
a.cc: In function 'int main()':
a.cc:8:52: error: conversion from 'std::shared_ptr<arrow::io::MemoryMappedFile>' to non-scalar type 'std::shared_ptr<arrow::io::FileInterface>' requested
std::shared_ptr<arrow::io::FileInterface> file = memory_mapped_file;
^~~~~~~~~~~~~~~~~~
We can resolve it by using virtual inheritance.