Trait sp_externalities::ExternalitiesExt

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

Extension for the Externalities trait.

Required methods

fn extension<T: Any + Extension>(&mut self) -> Option<&mut T>

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

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

Register extension ext.

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

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

Deregister and drop extension of T type.

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

Implementors

impl ExternalitiesExt for &mut dyn Externalities

impl<H, N> ExternalitiesExt for TestExternalities<H, N> where     H: Hasher,     H::Out: Ord + Codec,     N: ChangesTrieBlockNumber,