The Pedersen hash function is a builtin and has its own gas costs, not counted in terms of Cairo steps. You can find more information about it here: <https://docs.starknet.io/docs/Fees/fee-mechanism/>﻿


ㅤ
_This answer was originally posted on [Triality](https://triality.org/question/1084)_

Does anyone have information about the efficiency of the Pedersen hash in terms of steps/gas?


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/1084)_

How many Cairo steps does it take to compute one Pedersen hash?

I have a switch statment where I need to set two distinct, values so thought I would use a tuple  or a struct but I keep getting:

For a struct

`Expected a 'felt' or a pointer type. Got:<TYPE PATH> `

For a tuple

`Expected a 'felt' or a pointer type. Got:(felt,felt) `

This is with the unset tempvar being declared before the branching, and being set in each of the paths. 


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

A switch statement in Cairo lang to set two distinct values

Hi! I like writing my Cairo code in vim. However, I don't like that Cairo lang code has no auto-format and syntax highlighting (see screenshot):

![https://sun9-86.userapi.com/impg/oNPtr4oks9yNwg3MDoX8c5b-B4IBgK1DARpTbg/RJgXBHR3mEY.jpg?size=1242x682&quality=96&sign=3390ee79c30971ba0dc245122af04905&type=album](https://sun9-86.userapi.com/impg/oNPtr4oks9yNwg3MDoX8c5b-B4IBgK1DARpTbg/RJgXBHR3mEY.jpg?size=1242x682&quality=96&sign=3390ee79c30971ba0dc245122af04905&type=album)

I'm looking for a plugin to write Cairo contracts on Starknet in vim with all pretty formatting. Can you recommend any and how to install it as well?



Does anyone know a vim plugin for StarkNet smart contracts?

anybody manged to declare contracts with the new nile?

```
Error: AssertionError: Sender must be passed explicitly when making a direct declaration using --no_wallet.
```

I saw a hardhat issue aswel

must be an upstream thing

https://docs.starknet.io/docs/Blocks/transactions/#calculating-the-hash-of-a-v1-declare-transaction

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

An error “AssertionError: Sender must be passed explicitly when making a direct declaration using —no_wallet.” using the new nile?


According to [the doc](https://starknet.io/docs/how_cairo_works/cairo_intro.html#field-elements) a felt is a field element, ie any integer between in the range [0, P) with P = 2^251 + 17 \* 2^192 + 1.


On the other hand, the [range\_check\_ptr](https://starknet.io/docs/how_cairo_works/builtins.html#range-checks) checks that a felt is within [0, 2^128).


I don't understand this limitation : why not [0, 2^250) such that a felt is somehow a int250?


MWE:



```
%lang starknet

from starkware.cairo.common.math import assert_nn

@view
func foo{range_check_ptr}() -> ():
    alloc_locals
    local x
    %{ ids.x = PRIME - 10 %}
    assert_nn(a=x)
    return ()
end

```

this fails because of how the `assert_nn` and `range_check_ptr` are defined but I can't understand why it's design so:



```
Error at pc=0:0:
Got an exception while executing a hint.
    %{
        ^^
Cairo traceback (most recent call last):
contracts/main.cairo:6:6: (pc=0:13)
func foo{range_check_ptr}() -> ():
     ^**^
contracts/tmp.cairo:10:5: (pc=0:8)
    assert_nn(a=x)
    ^************^

Traceback (most recent call last):
  File "/Users/clementwalter/.pyenv/versions/3.9.13/envs/starksheet/lib/python3.9/site-packages/starkware/cairo/common/math.cairo", line 43, in <module>
    assert 0 <= ids.a % PRIME < range_check_builtin.bound, f\'a = {ids.a} is out of range.\'
AssertionError: a = 3618502788666131213697322783095070105623107215331596699973092056135872020471 is out of range.'})

```


ㅤ
_This question was originally posted on [Stack Overflow](https://stackoverflow.com/questions/72922293/why-does-range-check-ptr-chek-for-0-2128-instead-of-0-p-2)_

Why does range_check_ptr chek for [0, 2^128) instead of [0, P/2)

Is there a list of this compiled somewhere? Thanks


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/1075)_

Where can I find a list of decorators available in Cairo?

Does AA support bundling multiple operations at once?
---

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 (StarkNet) support bundling multiple operations at once?

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
```


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How many Cairo steps does it take to compute one Pedersen hash?

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