Would really like to understand how a full node for Starknet like pathfinder works

How does a full node like pathfinder work

Hey! I have a contract deployed on Testnet. Let's say its address is `0x1234`.

I want to get its ABI somehow, but I don't have the code of the contract, because it wasn't deployed by me.

I'm using StarkNet.py to interact with StarkNet.

Does anyone know the answer?

How to get the contract ABI using Starknet.Py?

Hello! This is day 10 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 “Bitwise operations”.  Perhaps you can help me?

```
// The bitwise builtin allows you to perform bitwise operations
// (and, or, xor) on integers up to 251 bits.
//
// The following code implements the function xor_last_hex_digits,
// which takes the two last hexadecimal digits and "xor"s them.
// For example, in 0x1234 the last two digits are 3 and 4,
// and their xor is 3^4=7.
//
// Fix the missing code and make sure it works.

%builtins bitwise

from starkware.cairo.common.bitwise import bitwise_and, bitwise_xor
from starkware.cairo.common.cairo_builtins import BitwiseBuiltin

// Returns the xor of the last two hexadecimal digits.
func xor_last_hex_digits{bitwise_ptr: BitwiseBuiltin*}(x: felt) -> (res: felt) {
    // Fix and uncomment the line below.
    // let (digit0) = ...

    let (shifted_digit1) = bitwise_and(x, 0xF0);
    tempvar digit1 = shifted_digit1 / 0x10;

    return bitwise_xor(digit0, digit1);
}

func main{bitwise_ptr: BitwiseBuiltin*}() {
    let (res) = xor_last_hex_digits(0x1234);
    assert res = 7;

    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 make Bitwise operations in Cairo Lang using %builtins bitwise, bitwise_xor?

When I try to transpile my contract using warp transpiler I get an error: `JavaScript heap out of memory`

![JavaScript heap out of memory error in Nethermind's warp transpiler](https://res.cloudinary.com/varga/image/upload/v1670423892/Screenshot_2022-11-30_at_7.32.34_PM_pazqli.png)

can anyone help?

update:
I ran this command 
```
export NODE_OPTIONS=--max-old-space-size=4096
```
before transpiling
still show the same error

- Node version is v16.16.0
- warp version  2.4.1
- I tried using node 18 but still same error occured
- I'm using an M1 Mac, 8gb RAM

I'm transpiling llampay contracts : [https://github.com/LlamaPay/llamapay/tree/master/contracts](https://github.com/LlamaPay/llamapay/tree/master/contracts)

The original LlamaPay has some unsupported features in Warp. And I fixed them:
- [LlamaPay.sol](https://pastebin.com/12pSdPBJ) 
- [LlamaPayFactory.sol](https://pastebin.com/DVeuvWKd)


Nethermind's warp error: JavaScript heap out of memory

Error compiling Pathfinder (rust)

Hey, is there a unsigned_div_rem supporting dividing by 2**128 ?

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

Is there a unsigned_div_rem supporting dividing by 2**128 ?

How to transpile multiple contracts at once using [Nethermind's warp](https://github.com/NethermindEth/warp)?

How to transpile multiple contracts at once using warp?

Hello guys, i was wondering what are the projects on starknet that plan to do the domain .stark  plz

I know there is starknet id, but is there any others ?

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

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