Trait ExternalitiesExt

pub trait ExternalitiesExt {
    // Required methods
    fn extension<T>(&mut self) -> Option<&mut T>
       where T: Any + Extension;
    fn register_extension<T>(&mut self, ext: T) -> Result<(), Error>
       where T: Extension;
    fn deregister_extension<T>(&mut self) -> Result<(), Error>
       where T: Extension;
}

Extension for the Externalities trait.

Required Methods

fn extension<T>(&mut self) -> Option<&mut T>

where T: Any + Extension,

Tries to find a registered extension and returns a mutable reference.

fn register_extension<T>(&mut self, ext: T) -> Result<(), Error>

where T: Extension,

Register extension ext.

Should return error if extension is already registered or extensions are not supported.

fn deregister_extension<T>(&mut self) -> Result<(), Error>

where T: Extension,

Deregister and drop extension of T type.

Should return error if extension of type T is not registered or extensions are not supported.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl ExternalitiesExt for &mut dyn Externalities

impl<H> ExternalitiesExt for TestExternalities<H>

where H: Hasher, H::Out: Ord + Codec,