Trait object serialization for rkyv.

Resources

Learning Materials

• The rkyv book covers the motivation, architecture, and major features of rkyv
• The rkyv discord is a great place to get help with specific issues and meet other people using rkyv

Documentation

• rkyv, the core library
• rkyv_dyn, which adds trait object support to rkyv
• rkyv_typename, a type naming library

Benchmarks

• The rust serialization benchmark is a shootout style benchmark comparing many rust serialization solutions. It includes special benchmarks for zero-copy serialization solutions like rkyv.

Sister Crates

• bytecheck, which rkyv uses for validation
• ptr_meta, which rkyv uses for pointer manipulation
• rend, which rkyv uses for endian-agnostic features

Example

```rust use rkyv::{ archivedvalue, ser::{ serializers::AlignedSerializer, Serializer, }, AlignedVec, Archive, Archived, Deserialize, Infallible, Serialize, }; use rkyvdyn::archivedyn; use rkyvtypename::TypeName;

[archive_dyn(deserialize)]

trait ExampleTrait { fn value(&self) -> String; }

[derive(Archive, Serialize, Deserialize)]

[archive_attr(derive(TypeName))]

struct StringStruct(String);

[archive_dyn]

impl ExampleTrait for StringStruct { fn value(&self) -> String { self.0.clone() } }

impl ExampleTrait for Archived { fn value(&self) -> String { self.0.asstr().tostring() } }

[derive(Archive, Serialize, Deserialize)]

[archive_attr(derive(TypeName))]

struct IntStruct(i32);

[archive_dyn(deserialize)]

impl ExampleTrait for IntStruct { fn value(&self) -> String { format!("{}", self.0) } }

impl ExampleTrait for Archived { fn value(&self) -> String { format!("{}", self.0) } }

fn main() { let boxedint = Box::new(IntStruct(42)) as Box; let boxedstring = Box::new(StringStruct("hello world".to_string())) as Box; let mut serializer = AlignedSerializer::new(AlignedVec::new());

let int_pos = serializer.serialize_value(&boxed_int)
    .expect("failed to archive boxed int");
let string_pos = serializer.serialize_value(&boxed_string)
    .expect("failed to archive boxed string");
let buf = serializer.into_inner();

let archived_int = unsafe { archived_value::<Box<dyn SerializeExampleTrait>>(buf.as_ref(), int_pos) };
let archived_string = unsafe { archived_value::<Box<dyn SerializeExampleTrait>>(buf.as_ref(), string_pos) };
assert_eq!(archived_int.value(), "42");
assert_eq!(archived_string.value(), "hello world");

let deserialized_int: Box<dyn SerializeExampleTrait> = archived_int.deserialize(&mut Infallible).unwrap();
let deserialized_string: Box<dyn SerializeExampleTrait> = archived_string.deserialize(&mut Infallible).unwrap();
assert_eq!(deserialized_int.value(), "42");
assert_eq!(deserialized_string.value(), "hello world");

} ```