Try to make the following steps:

### 1. Change package.json

```cairo
"browserslist": {
    "production": [
      "chrome >= 67",
      "edge >= 79",
      "firefox >= 68",
      "opera >= 54",
      "safari >= 14"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  }
```

in package.json

The issue is that native BigInt support is required atm

### 2. Delete node modules

This worked like a charm if you delete `node_modules`

Newton

I made an example using [this library with react](https://github.com/fracek/starknet-react-example), everything is working fine in development, but in production, it looks like starknet.js is throwing a type error. You can [open this page](http://starknet-react-example.vercel.app/) to see the error more in detail.

To reproduce locally:

- Clone my example repo
- Build with `yarn run build`
- Serve production build with `yarn run serve`

Based on this [Github thread](https://github.com/0xs34n/starknet.js/issues/37)

How do I use Create React App in StarknetJS?

What is the maximum value a `uint` can store?

I need to understand a couple of things:

1. What is the maximum value `a felt` and `uint` can store?
2. Are the maximum values stored in felt and uint the same?

---
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What is the maximum value an uint and felt can store in Cairo Language?

Hi, just saw starknet.js latest is now 4.4 and not 3.x anymore. Do you plan to move the that release at what horizon? Is there some known issues staying with 3.x and working with starknet-react?

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

Is there any issue between using 4.4 and 3.x starknet.js?

heyy guys, running into a problem

I have this code :
```struct TokenLedger:
   member token_address : felt
   member drip_amount : Uint256
   member balance : Uint256
end

@storage_var
func tokens_ledger(index : felt) -> (tokenLedger : TokenLedger):
end```

```let (ledger : TokenLedger) = TokenLedger(token_address, drip_amount, balance)
tokens_ledger.write(index, ledger)```
But am getting this error :

```faucet.cairo:94:34: Unexpected '.' after '__main__.TokenLedger' which is struct.
let (ledger : TokenLedger)  = TokenLedger(token_detail.token_address, token_detail.drip_amount, curr_balance)
                                ^*********^

       Failed

Error in plugin Starknet: Failed compilation of 1 contract.```

How to write a struct in storage?

## What is Kakarot, the zkEVM written in Cairo?


What is Kakarot, the zkEVM written in Cairo?

Hi,

any idea what this could be caused by? This function is mentioned only once in the whole codebase. I’m trying to do protostar build

```python
Redefinition of '__wrappers__.get_pool_balance.__wrapped_func'.

func get_pool_balance{syscall_ptr : felt*, pedersen_ptr : HashBuiltin*, range_check_ptr}(
```

This error always appears with the first function it encounters that is annotated with either @view or @external

Can be reproduced in the repro-redefinition branch of [https://github.com/CarmineOptions/carmine-protocol.git](https://github.com/CarmineOptions/carmine-protocol.git)

Has anyone seen this error in proto? Redefinition of *`wrappers.*ourfunctionname.__wrapped_func__’`?

Any idea what this could be caused by?

>Hello! This is day 5 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 “Revoked references”. Can you run these 6 steps and write down what you see?

```
// The scope of some types of references in Cairo (e.g., return values of
// functions and temporary variables) is somewhat restricted.
// For example, a call to another function may revoke those references.
//
// 1. Try to run the following code. You should get an error that `x` was revoked
//    (this is because of the second call to `foo`).
// 2. In simple cases, like this one, the compiler can solve this automatically
//    if the "alloc_locals" keyword is used within the function's scope.
//    Add "alloc_locals;" to the beginning of main(), and make sure the code works.
// 3. To understand what happens behind the scenes, replace "alloc_locals;" with
//    "ap += SIZEOF_LOCALS;" - this command allocates memory cells for local variables
//    (you'll need them below) but doesn't enable the mechanism that
//    automatically resolves revoked references.
//    Trying to run the code now should result in the original error.
// 4. Solve the problem manually by copying the value of `x` to a local variable
//    (e.g., "local x2 = x;"). Local variables are not revoked when functions
//    are called.
//    You can read more about local variables [here](https://www.cairo-lang.org/docs/how_cairo_works/consts.html#local-vars).
// 5. You can even use the same name: "local x = x;".
//    This is called "reference rebinding", where the meaning of `x` changes:
//      Before this line, `x` refers to the return value.
//      After that, `x` refers to the local variable.
// 6. A shorter syntax is "let (local x) = foo(10);" which achieves the same goal.
//    Try it!

%builtins output

from starkware.cairo.common.serialize import serialize_word

// Returns a^3 for a != 0 and 1 otherwise.
func foo(a) -> (res: felt) {
    if (a == 0) {
        return (res=1);
    } else {
        return (res=a * a * a);
    }
}

// Outputs the value 10^3 + 5^3.
func main{output_ptr: felt*}() {
    let (x) = foo(10);
    let (y) = foo(5);
    serialize_word(x + y);
    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)*



Cairo Lang / StarkNet: What are Revoked references? What is alloc_locals?

Hey, is there anyway to debug Cairo contracts in hardhat environment? Something like hardhat console in Solidity?

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How do I use Create React App in StarknetJS?

1 answers

1. Change package.json

2. Delete node modules

Your answer

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