Question about `ApplyBackend` for v1.0.0

[mrLSD]

Question

In the previous versions (for example v0.41) was trait:

/// EVM backend that can apply changes.
pub trait ApplyBackend {
	/// Apply given values and logs at backend.
	fn apply<A, I, L>(&mut self, values: A, logs: L, delete_empty: bool)
	where
		A: IntoIterator<Item = Apply<I>>,
		I: IntoIterator<Item = (H256, H256)>,
		L: IntoIterator<Item = Log>;
}

Current version v1.0.0-alpha.2 completely rafactored.

❓ Question is: as far as we will need to transfer from v0.x ➡️ v1.0 we need to understand clearly how to do that. Actually for ApplyBackend it's unclear. It seems apply logic was completely changed. I would be pleased for some advice on that point.

[mrLSD]

As it is provided new trait: https://github.com/rust-ethereum/evm/blob/master/src/backend/mod.rs

And it is really unclear, because previously:
https://github.com/rust-ethereum/evm/blob/v0.36.0/src/backend/mod.rs#L30C13-L30C13

for apply operation was provided:

pub enum Apply<I> {
	/// Modify or create at address.
	Modify {
		/// Address.
		address: H160,
		/// Basic information of the address.
		basic: Basic,
		/// Code. `None` means leaving it unchanged.
		code: Option<Vec<u8>>,
		/// Storage iterator.
		storage: I,
		/// Whether storage should be wiped empty before applying the storage
		/// iterator.
		reset_storage: bool,
	},
	/// Delete address.
	Delete {
		/// Address.
		address: H160,
	},
}

[sorpaas]

This (https://github.com/rust-ethereum/evm/blob/master/src/backend/overlayed.rs#L57) is probably what you need. The idea is the same, but instead of an enum specifying individual actions, right now we have maps that you iterate individually.

See also https://github.com/rust-ethereum/evm/blob/master/jsontests/src/in_memory.rs for a in-memory implementation with apply logic.