Using TypeScript to create a generic function that returns a null value

In my Typescript code, I have the following function: In C#, you can use default(T), but I'm not sure what the equivalent is in Typescript.

public Base {
...
}


public Get<T extends Base>(cultura: string): T[] 
{

    let res = null;

    try
    {

    }
    catch (ex)
    {
        throw ex;
    }

    return res;
}

When trying to return a null value, I encounter an error. Even assigning null to a variable and then returning that variable results in the same error.

The error message states: The 'null' type cannot be assigned to the type T[].

This is the error screenshot:

https://i.stack.imgur.com/L8PgN.png

How can I address this issue in TypeScript?

Answer №1

If you have strict null checks enabled, it means that you are not allowed to assign null to a variable or return value unless it has been explicitly stated as a possibility. You can either disable strict null checks by setting strictNullChecks: false in your tsconfig.json file, or adjust the return type to T[] | null. Alternatively, it is recommended to simply return an empty array instead of null.

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