polydat-derive

The #[polydat_node] procedural macro for Polydat. It turns one typed free function into a Polydat node: the node struct, its constructor, the PolydatNode implementation with the evaluation forms the signature allows on every engine, and the link-time registration that makes the function callable from Polydat source.

Most users never depend on this crate directly. The polydat facade re-exports the attribute as polydat::polydat_node, and the macro emits paths under polydat::, so a crate that defines nodes depends on polydat and writes:

/// A rotated-xor checksum of two words.
#[polydat::polydat_node(category = Math)]
fn host_checksum(a: u64, b: u64) -> u64 {
    a.rotate_left(7) ^ b.wrapping_mul(0x9E37_79B9_7F4A_7C15)
}

The function's doc comment becomes the node's description and help. Each argument is classified by its type: per-cycle wires (scalars, strings, bytes, JSON, typed vectors, SIMD registers, host types), Const<T> workload constants captured at construction, &[T] variadic arguments, and setup state derived once from the constants. A single return is one output, a tuple is several named outputs, Result runs once at construction, and Value is polymorphic.

Documentation

The rustdoc on docs.rs lists every argument shape, return shape, and attribute parameter the macro accepts. The embedding guide shows host-defined nodes and value types in a running program.

License

Apache-2.0.