'prevSearch' in ToOptions. Is this behavior intended?

[LuiGeeDev]

I had a validateSearch error when I passed undefined to 'type' parameter. Arktype didn't allow undefined on optional parameter.

<Link
  search={(previous) => ({ ...previous, type: undefined })}
  to="/{-$locale}"
>
  {someButton}
</Link>

So I tried to delete it from previous search.

<Link
  search={(previous) => {
    delete previous.type;
    return previous;
  }}
  to="/{-$locale}"
>
  {someButton}
</Link>

Then I found that this also removes the search param in the url. So I solved it like below.

<Link
  search={(previous) => {
    const nextSearch = { ...previous };
    delete nextSearch.type;
    return nextSearch;
  }}
  to="/{-$locale}"
>
  {someButton}
</Link>

I know it is not recommended to modify the parameter object in the function, but I really didn't expect prevSearch is actually connected to the current url state. I thought it's just an object with current search params values. Didn't test prevParams, but I guess it works same.

Is this a intended behavior? Any performance issues if this prev object is a copied one?