metatype

Docs

Helper methods to determine whether a type is TraitObject, Slice or Concrete, and work with them respectively.

Examples

```rust asserteq!(usize::METATYPE, MetaType::Concrete); asserteq!(any::Any::METATYPE, MetaType::TraitObject); assert_eq!(<[u8]>::METATYPE, MetaType::Slice);

let a: Box = Box::new(123); asserteq!((&*a).metatype(), MetaType::Concrete); let a: Box = a; asserteq!((&*a).metatype(), MetaType::TraitObject);

let a = [123,456]; asserteq!(a.metatype(), MetaType::Concrete); let a: &[i32] = &a; asserteq!(a.metatype(), MetaType::Slice);

let a: Box = Box::new(123); // https://github.com/rust-lang/rust/issues/50318 // let meta: TraitObject = (&*a).meta(); // println!("vtable: {:?}", meta.vtable); ```

Note

This currently requires Rust nightly for the raw and specialization features.

License

Licensed under Apache License, Version 2.0, (LICENSE.txt or http://www.apache.org/licenses/LICENSE-2.0).

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.