Determining the data type of a generic variable within an Angular component

I'm currently in the process of developing a versatile component that can handle data of only two specific types:

interface X{
    name: string,
    path: string,
    type: string,
}

interface Y{
    name: string,
    path: string,
}

Both types X and Y share two common properties, with X having an extra one. At this point, I've defined the type as follows:

export class MyComponent<T extends X | Y> implements OnInit{
    @Input() data: T[];
    func(item: T){
        let temp = this.data.find(x => x.name === item.name);
        <<....some code....>>
    }
}

When calling this from the parent component, it looks like this:

<my-component [data]="xList"></my-component>     <!-- xList: X[] -->
<my-component [data]="yList"></my-component>     <!-- yList: y[] -->

Everything seems to be functioning correctly, but I'm unsure if <T extends X | Y> is the most suitable method for achieving this. Can anyone offer suggestions on the best approach? Is it possible to declare something like where T implements X | Y in Typescript?

Alternatively, should I simply use @Input() data: any[]; instead?

Answer №1

This appears satisfactory to me, though I would specifically use T extends Y. This is because the presence of the type key on X seems excessive, potentially causing issues if an array of Y is inputted and the component interferes with the type key.

Answer №2

It is unlikely that the Angular framework will recognize the generic argument T when instantiating MyComponent. One workaround could be to obtain an instance of the component at runtime and attempt to manually set the generic type, although this may not have any effect since MyComponent would already be instantiated with the @Input() data property set.

Alternatively, you could consider defining @Input() data: X[] | Y[] directly in your component.

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