Function near_sdk::env::promise_then

pub fn promise_then(
    promise_idx: PromiseIndex, 
    account_id: AccountId, 
    method_name: &[u8], 
    arguments: &[u8], 
    amount: Balance, 
    gas: Gas
) -> PromiseIndex

Attaches the callback that is executed after promise pointed by promise_idx is complete.