我试图让getResults
函数返回正确的类型,但目前仍有以下问题:
interface IResponse<T> {
result: T;
}
type FnType<P, R> = (params: P) => R;
const r1: IResponse<string[]> = { result: ['123'] };
const r2: IResponse<number[]> = { result: [456] };
const getResults = <T, R extends IResponse<T[]>, P>(fn: FnType<P, R>, params: P): T[] => {
return [
...fn(params).result,
...fn(params).result
];
};
const getValue = <T>(r: IResponse<T>) => r;
// returned type is unknown[]
// how can we make it return string[]?
getResults(getValue, r1);
// returned type is unknown[]
// how can we make it return number[]?
getResults(getValue, r2);
代码只是一个示例,在production getResults
中,函数用于合并分页请求的结果(本例中fn
是一个请求函数)