How to swap array elements using destructuring in Solidity? - solidity

Question

I want to delete data from an array. But deleting data from a particular array index creates a gap in the array. Hence, I am swapping the array[i] with array[array.length-1] and popping out the array. I tried to do it with a destructuring technique that is supported in Solidity yet it turns out the values do not tend to swap. While swapping using the "temp" variable seems to work perfectly fine but it consumes more gas.
There's a warning that solidity throws which I am not able to understand.
Warning: This assignment performs two copies to storage. Since storage copies do not first copy to a temporary location, one of them might be overwritten before the second is executed and thus may have unexpected effects. It is safer to perform the copies separately or assign to storage pointers first.
Can anyone help?
Please find the code below:
struct Details{
uint256 id;
address walletAddress;
string fullName;
uint256 phoneNumber;
string residentialAddress;
}
Details [] public userDetails;
function deleteData(uint256 _id) public onlyOwner returns(string memory){
for(uint256 i=0;i<userDetails.length;i++)
{
if (userDetails[i].id==_id){
(userDetails[i],userDetails[userDetails.length-1])=(userDetails[userDetails.length-1],userDetails[i]);
userDetails.pop();
}
}
}

Answer 1

You can just assign the last item to the place of the deleted one (effectively duplicating the last item for the moment), and then delete the last item.
if (userDetails[i].id == _id) {
userDetails[i] = userDetails[userDetails.length-1];
userDetails.pop();
break;
}