proc_macro for generating highly optimized V8 functions from Deno ops.
// Declare an op.
#[op]
pub fn op_add(_: &mut OpState, a: i32, b: i32) -> Result<i32, AnyError> {
Ok(a + b)
}
// Register with an extension.
Extension::builder()
.ops(vec![op_add::decl()])
.build();