When used as the type for a function parameter,readonly ensures that the parameter will not be mutated inside the function.

Thecolumns anddata array inputs are never modified bytable-core. They should thus be marked asreadonly to make this contract explicit. This allows developper to rely on the guarantee they can pass in static objects.

Here's an example where this is useful:

constComponent=()=>{const{ data}=useQuery({ ...})consttable=useReactTable({ data, ...})

In a case like this,data comes from thetanstack/query cache, and as such must be immutable. IfuseReactTable can guarantee that it won't modify the array we pass in, then we can passdata directly.

Summary by CodeRabbit

• Refactor

  • Table options now use readonly arrays. Both data and columns accept readonly arrays, and related getters return readonly arrays. This enforces immutability and improves type safety. If your code mutates these arrays or relies on mutable types, update it to create new arrays instead.

• Documentation

  • API docs updated to reflect readonly types for data and columns in the Table APIs.