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![]() This procedural macro attribute provides a simple way to declare a trait with a set of operations that later users can partially implement, providing compile-time `HAS_*` boolean associated constants that indicate whether a particular operation was overridden. This is useful as the Rust counterpart to structs like `file_operations` where some pointers may be `NULL`, indicating an operation is not provided. For instance: #[vtable] trait Operations { fn read(...) -> Result<usize> { Err(EINVAL) } fn write(...) -> Result<usize> { Err(EINVAL) } } #[vtable] impl Operations for S { fn read(...) -> Result<usize> { ... } } assert_eq!(<S as Operations>::HAS_READ, true); assert_eq!(<S as Operations>::HAS_WRITE, false); Signed-off-by: Gary Guo <gary@garyguo.net> Reviewed-by: Sergio González Collado <sergio.collado@gmail.com> [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda <ojeda@kernel.org> |
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.. | ||
alloc | ||
bindings | ||
kernel | ||
macros | ||
.gitignore | ||
bindgen_parameters | ||
compiler_builtins.rs | ||
exports.c | ||
helpers.c | ||
Makefile |