You are most likely attempting to reference the `Id` struct before it has been declared. Instead of:


`@storage_var`


`func id(key: felt) -> (id: Id):`


`end`


`﻿`


`struct Id:`


 `member x: felt`


 `member y: felt`


 `member z: felt`


`end`


put the `Id` struct above the `@storage_var`:


`struct Id:`


 `member x: felt`


 `member y: felt`


 `member z: felt`


`end`


`﻿`


`@storage_var`


`func id(key: felt) -> (id: Id):`


`end`


ㅤ
_This answer was originally posted on [Triality](https://triality.org/question/595)_

I am doing the storage02.cairo exercise in starklings and am getting the following error. Does anyone know what it means?


`autogen/starknet/storage_var/id/decl.cairo:14:14: Expected '__main__.Id' to be a struct. Found: 'future'.`


 `id : Id`


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/595)_

Cairo: Expected '__main__.Id' to be a struct. Found: 'future'

I'm aware of starknet having a common--and unsafe--keccak library. Either way, I was wondering if there's a way to mimic the behavior of solidity's 
```
keccak256(abi.encode(parameters))
```
Thank you very much.

Is there a Cairo equivalent to Keccak256(abi.encode(parameters))?

Hello! This is day 9 of the 17 days of the Cairo Challenge. And I have no idea how to solve the [playground](https://www.cairo-lang.org/playground/) exercise “Field Elements 2”.  Perhaps you can help me?

```
// As you saw in the previous challenge, the operator '/' does not denote
// truncated (i.e., rounding down) integer division as in other programming
// languages. Instead, one can use library functions such as
// unsigned_div_rem().
//
// Note that unsigned_div_rem() does not work for negative numbers.

%builtins output range_check

// Import unsigned_div_rem() from the math module.
from starkware.cairo.common.math import unsigned_div_rem
from starkware.cairo.common.serialize import serialize_word

func main{output_ptr: felt*, range_check_ptr}() {
    let (q, r) = unsigned_div_rem(value=12, div=3);
    // Output the quotient (12 // 3).
    serialize_word(q);
    // Output the remainder (12 % 3).
    serialize_word(r);

    // Add code that outputs the quotient and remainder of 13 / 3 in addition to 12 / 3 here.

    return ();
}
```

---

> Answers to this question are a part of the ✨ 17 days of Cairo Lang with Playground & Newton. ✨
> 

*Vote for your favorite answer - the best answer will win a $10 award. A new day – a new reward! During the next 17 days, our goal is to attract more developers to the Cairo language and to systematize the knowledge of Cairo lang. [Read rules](https://www.notion.so/17-days-of-Cairo-Lang-with-Newton-550dfcda6a2d449ca468be293c776578)*

How to divide felt in Cairo Lang using unsigned_div_rem?

Does AA support "Burner Accounts" so I can connect a new account to a new dApp without worrying about losing all my funds?

---

This question is participating in [Newton Bounties | Incentivized Test Program](https://www.notion.so/Newton-Bounties-Incentivized-Test-Program-94322ad48e7d40a3adcf36f6b26174cd) Every verified valid question gets $10 USDC (mainnet)

Does Account Abstraction support "Burner Accounts"?

Hello! I'm trying to deploy a new account through cmd "starknet deploy_account", result seems fine but the tx is never picked up (15 min now while there are blocks being produced on Goerli). Status of this tx is "received". 
Is this normal?

_This question was originally posted on [StarkNet Discord](https://www.newton.so/view?tags=discord)_

Status “received” while deploying starknet transaction. Is it ok?

Hi, I'm using pytest for testing cairo contract. I found that a simple starknet setup and initial call for contract cost 34 seconds. Is there a way to accelerate test?

upd: yes, [this works](https://www.notion.so/Hi-I-m-using-pytest-for-testing-cairo-contract-I-found-that-a-simple-starknet-setup-and-initial-ca-db2282fc02f2463aadaf63eac655df6f). but I found that compiling contract cost 7s and deploying contract cost 25s. These two operations are the most time-consuming

 Is there a way to accelerate pytest for cairo contract?

Hey, the docs always use `await` before methods, but when I try to run those scripts I get an error. 

Anyone could help?

How to use await in StarkNet.py?

Hello friends, is there a way to cache context + StarkNet state? Or save and load on a fresh network. I'm looking at ways to avoid deploying the same contracts every time before running tests.

_This question was originally posted on [StarkNet Discord](https://www.newton.so/view?tags=discord)_

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Cairo: Expected 'main.Id' to be a struct. Found: 'future'

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