Hey,

You can only return felt, so if you want to return an array you have to use another `storage_var`.  For exemple if I want to return an array you may do something like this:
```
struct Array {
    array_index: felt,
    len: felt,
}

@storage_var
func get_array() -> (array: Array) {
}

@storage_var
func array(array_index: felt, index: felt) -> (value: felt) {
}
```
As you can see, the `storage get_array()` will return a struct of type `Array` which contain the `array_index and len` of the array. Then use it in `storage_var array()`  to get the corresponding value. Since you have the `len` you can create a recursion to the storage var to get all the element of the array of index `array_index`.


Hey guys,
I got this error `The return type of storage variables must be a felts-only type (cannot contain pointers)` when when compiling this:
```
struct MultipleLinear {
    number_of_features: felt,
    coef_s: felt*,
    intercept_: felt,
}
@storage_var
func solution_storage(address: felt) -> (solution: MultipleLinear) {
}
```
Apparently **storage can only return felt**? So what would be the solution if I want it to return an array or a struct that contains felt*?

storage for array

You can try something like this (cf Starkgate code):

```
 uint256 constant UINT256_PART_SIZE_BITS = 128;
 uint256 constant UINT256_PART_SIZE = 2**UINT256_PART_SIZE_BITS;
```

And payload will be like this :

```
uint256[] memory payload = new uint256[](3);
payload[0] = l2Recipient;
payload[1] = amount & (UINT256_PART_SIZE - 1);
payload[2] = amount >> UINT256_PART_SIZE_BITS;
```

Then on L2 you will received amount as 2 felt, high and low. Then you juste have to use it with ` let (amount: Uint256) =Uint256(low=low, high=high)`  And that's it.





How can I send a Uint256 amount of ERC20 tokens from L1 to starknet?
I have "amount" as a uint256 on L1 but how should I build my payload for "`sendMessageToL2`" to match the Uint256 format of Cairo?

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How can I send a Uint256 amount of ERC20 tokens from L1 to starknet? And how should I build my payload for "sendMessageToL2" to match the Uint256 format of Cairo?

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