Feature Suggestion: Mimic `Ecto.Multi` for batch / multicalls

[sitch]

Example

Ethers.Multi.new()
|> Ethers.Multi.append(:my_transaction_1, ERC20.balance(x))
|> Ethers.Multi.append(:my_transaction_2, ERC20.balance(y))
|> Ethers.Multi.batch_call(options)

Could use the same container for multicalls, i.e.:

Ethers.Multi.multicall3(multi, options)

[alisinabh]

Hey @sitch,
This is good idea. Are you interested in the initial implementation?

[sitch]

I would be happy to!

And just to clarify — from my perspective the main utility of this pattern is to give a name to a transaction so its easier to understand output compared to: {:ok, [ok: _, ok: _, …]}.

So the main features would be:

1. Execute the multi as a batch call
2. Execute the multi as a multicall
3. Execute the multi sequentially

The last one (#3) I don’t personally see much utility in, but that reducer pattern is kind of at the heart of how Ecto.Multi works, so I figure might as well include it? It would behave more like batch where block reference would not be guaranteed, only execution order.

[alisinabh]

Combining 1 with 2 is potentially hard cause a batch call might include other rpc actions too. For the first version I think it makes sense to focus on 2 (multical support) and then figure out batch and sequential calls.