TEP-137: Jetton Wallet Balance Query

[0kenx]

No description provided.

[mr-tron]

It will never be accepted.

For example in situations where the smart contract knows that no outbound transfer can happen between the get_balance call and the get_balance_response reply (for example when a smart contract queries its own balance), the smart contract can know the minimum amount of Jetton tokens it holds.

In this case contract should block processing all over messages which can change balance until it receives get_balance_response. In can require up to few minutes. Very easy to make mistake for developers without big experience in async networks.

[0kenx]

In this case contract should block processing all over messages which can change balance until it receives get_balance_response. In can require up to few minutes.

This is simply not true. In my example where the contract just wants to make sure its balance is greater than x, as long as the contract doesn't transfer funds out (i.e. the balance doesn't reduce) it can keep processing other messages, and if it receives a response that is at least x it can proceed.

Very easy to make mistake for developers without big experience in async networks.

As I have stated multiple times in the document, it should up to the dapp developer to correctly use this feature. You can't cripple experienced async developers for the reason that the feature can "potentially be misused by inexperienced developers". We can mitigate the misuse risk by providing clear explanations in the documentation (which I have already done in the standard).

[0kenx]

Bumping this since we've again run into issues related to this design flaw.

Saying "you can't query the balance since the balance might change" is equivalent to your bank or credit card company refusing to give you an account statement because "someone might have charged your card in the meantime".