You can use get_label_location() on the name of the function, and then pass this in and use it to call the function.


ie. let (function_name) = get_lable_location()


map(function_name, array)


This also works with storage variables since they are represented as functions.


ㅤ
_This answer was originally posted on [Triality](https://triality.org/question/313)_

How would I go about passing a function as a parameter to a function. Ex map(function, array)


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/313)_

Cairo Passing Functions

How can I prepare my Cairo lang project for an audit?

Hello! This is Day 2 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 “Functions”. Perhaps you can help me?

```python
// The following code is missing the function `add1`.
// 1. Click on "Run" to see the error.
// 2. Write the function `add1`, based on `add1_square`, so
//    that the program terminates successfully.
//
// Note that `add1` doesn't have to call other functions.
//
// You can learn more about functions [here](https://www.cairo-lang.org/docs/how_cairo_works/functions.html).

// Write your code here.

func add1_square(x: felt) -> (x: felt) {
    // Call `add1` and unpack the result into `z`.
    let (z) = add1(y=x);
    return (x=z * z);
}

func main() {
    // Call `add1_square` and save the result into `res`.
    let (res) = add1_square(x=12);

    // Verify the computation.
    assert res = (12 + 1) * (12 + 1);
    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 write a function in Cairo Lang (StarkNet)?

Hi ! Is there something going on the testnet? The block time remains the same, but I have to wait several dozen minutes for my transactions to be accepted

And so, most of the time, the gas price changes a lot between the moment I send the transaction, and its execution, thus I'm getting the `Actual fee exceeded max fee` error quite often

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

Is there something going on the testnet StarkNet?

hi all. If I want to use starkex do I have to deploy my custom starkex contracts ?
however in my understanding startex is a protocol where I have to intergrate my dapp specific tx, isn't it ?
in the playground I saw there're some preimplemented tx like ERC20 interface 
is starknet a starkex with an integrated VirtualMachine ?

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

If I want to use starkex do I have to deploy my custom starkex contracts?

I have a struct with : 

```struct Binary:
felt a:
felt* b:
```

How to return this in a view function?
I see this error:
```
Can't identify return variable
```


how to return struct

Hey, I want to concatenate two arrays with known sizes in Cairo lang.
Is there any simple way how to do it? Can you share some of your code?

Is there any simple way to concat two arrays with known sizes in Cairo?

![img](https://sun9-13.userapi.com/impg/9YrwMdCKAVbgBRKmMdGysFrP3qhbHWBiTNgp3A/64s3EVNAEpE.jpg?size=1158x874&quality=96&sign=f55c859f079b65212bc744b47e7bb7af&type=album)
Is there a plan to get better visibility when a transaction got received but not placed into a block?
For the moment we only know that it is RECEIVED but have no clue if it’s been discarded because of missing constructor params or if it’s just late:

```python
{
	transaction_hash: '0x3d26af3d7a8f17ea28c2a71a250fd8c5dcd162b779051fd36a3bfcd9f130fab',
	actual_fee: undefined,
	status: 'RECEIVED',
	status_data: undefined,
	messages_sent: [],
	events: [],
	l1_origin_message: undefined
}
```

upd: I noticed we are notified when we make an error, but:

1. we don’t know what’s happening between `RECEIVED` and `REJECTED | ACCEPTED_ON_L2`, it’d be nice to be able to monitor a bit more preceisely where’s the transaction in the pipeline

2. the error message is often cryptic and not human readable, ex:

```python
Error: REJECTED: TRANSACTION_FAILED
Error at pc=0:1073:
An ASSERT_EQ instruction failed: 9:6 != 9:5.
```

Is there a way / tool to be able to debug this kind of failed transactions?

Popular tags

Cairo Passing Functions

1 answers

Your answer

Related

You may find useful