ink_env

Trait Environment

pub trait Environment: Clone {
    type AccountId: 'static + Codec + MaxEncodedLen + CodecAsType + Clone + PartialEq + Eq + Ord + AsRef<[u8]> + AsMut<[u8]>;
    type Balance: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + Into<U256> + FromLittleEndian;
    type Hash: 'static + Codec + MaxEncodedLen + CodecAsType + Copy + Clone + Clear + PartialEq + Eq + Ord + AsRef<[u8]> + AsMut<[u8]>;
    type Timestamp: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + FromLittleEndian;
    type BlockNumber: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + FromLittleEndian;
    type EventRecord: 'static + Codec;

    const NATIVE_TO_ETH_RATIO: u32;

    // Provided method
    fn native_to_eth(value: Self::Balance) -> U256 { ... }
}
Expand description

The environmental types usable by contracts defined with ink!.

The types and consts in this trait must be the same as the chain to which the contract is deployed to. We have a mechanism in cargo-contract that attempts to check for type equality, but not everything can be compared.

Required Associated Constants§

const NATIVE_TO_ETH_RATIO: u32

The ratio between the decimal representation of the native Balance token and the ETH token.

Required Associated Types§

type AccountId: 'static + Codec + MaxEncodedLen + CodecAsType + Clone + PartialEq + Eq + Ord + AsRef<[u8]> + AsMut<[u8]>

The account id type.

type Balance: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + Into<U256> + FromLittleEndian

The type of balances.

type Hash: 'static + Codec + MaxEncodedLen + CodecAsType + Copy + Clone + Clear + PartialEq + Eq + Ord + AsRef<[u8]> + AsMut<[u8]>

The type of hash.

type Timestamp: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + FromLittleEndian

The type of a timestamp.

type BlockNumber: 'static + Codec + CodecAsType + Copy + Clone + PartialEq + Eq + AtLeast32BitUnsigned + FromLittleEndian

The type of block number.

type EventRecord: 'static + Codec

TODO comment

Provided Methods§

fn native_to_eth(value: Self::Balance) -> U256

Converts from the generic Balance type to the Ethereum native U256.

§Developer Note

pallet-revive uses both types, hence we have to convert in between them for certain functions. Notice that precision loss might occur when converting the other way (from U256 to Balance).

See https://github.com/paritytech/polkadot-sdk/pull/9101 for more details.

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§