I am wondering if the smart contract is able to return the previous value of its global state.
For example, one contract is counting the number of opted-in users and recording the number into one of its global states. The contract, we assume, is created on round 12345, and it keeps running to round 23456. Generally, the contract records the state on round 23456, but I am curious about the number of users opted-in to contract on round 20000. So, a function that searching for the previous state of the contract is required.
Is there any function could do that kind of thing?