Trait concordium_std::HasContractState

pub trait HasContractState<Error: Default = ()> where
    Self: Read,
    Self: Write<Err = Error>,
    Self: Seek<Err = Error>, {
    type ContractStateData;
    fn open(_: Self::ContractStateData) -> Self;
    fn size(&self) -> u32;
    fn truncate(&mut self, new_size: u32);
    fn reserve(&mut self, len: u32) -> bool;
}

A type that can serve as the contract state type.

Associated Types

type ContractStateData

Required methods

fn open(_: Self::ContractStateData) -> Self

Open the contract state. Only one instance can be opened at the same time.

fn size(&self) -> u32

Get the current size of contract state.

fn truncate(&mut self, new_size: u32)

Truncate the state to the given size. If the given size is more than the current state size this operation does nothing. The new position is at most at the end of the stream.

fn reserve(&mut self, len: u32) -> bool

Make sure that the memory size is at least that many bytes in size. Returns true iff this was successful. The new bytes are initialized as 0.

Implementors

impl HasContractState<()> for ContractState

type ContractStateData = ()

impl<T: AsMut<Vec<u8>> + AsMut<[u8]> + AsRef<[u8]>> HasContractState<ContractStateError> for ContractStateTest<T>

type ContractStateData = T