[英]How to specialize a generic type in object literal?
// a.ts
interface Config {
selector?: <T>(httpResponse: HttpResponse<T>) => unknown;
}
export function factory(options: Config): something {
// use options to return something
}
// another file b.ts
// I have a type for res only here(b.ts), and I want to use it to specialize type T
import { factory } from 'a.ts';
factory({
selector: res => res.data.data; // error: Property 'data' does not exist on type 'T'
});
My question is: How to pass a specified type in the config object literal, so that generic type T can be specialized?我的问题是:如何在配置 object 文字中传递指定的类型,以便可以专门化泛型类型 T?
I don't know what your exact use case is but you can add the type to your interface like this:我不知道您的确切用例是什么,但您可以将类型添加到您的界面,如下所示:
interface Config<T> {
selector?: (httpResponse: T) => unknown;
}
function factory(options: Config<{ data: { data: string } }>) {
// use options to return something
return options;
}
factory({
selector: (res) => res.data.data,
});
Make factory
to generic function, and we can pass "T" of factory
to Config
what also is a generic object.将factory
设为通用 function,我们可以将factory
的“T”传递给Config
,这也是通用 object。
Start from Config
interface, make it become generic interface.从Config
接口开始,使其成为通用接口。
interface Config<T> { // Generically for whole interface
selector?: (httpResponse: HttpResponse<T>) => unknown;
}
The next, factory
function:接下来, factory
function:
export function factory<T>(options: Config<T>): something { // return type is "T" or something ?
// use options to return something
}
We pass type "T" from factory
to Config
.我们将类型“T”从factory
传递给Config
。
Finally, an example:最后,举个例子:
b.ts b.ts
export type ApiResponse = {
data: {
username: string;
}
}
Usage of factory工厂使用
factory<ApiResponse>({
selector: res => res.data.data.username, // typehint for the `res`, I try with HttpResponse is AxiosResponse
});
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.