slice
slice
Accepts an object of type T and a single key or an array of keys (K extends keyof T).
Constructs new object based on provided keys.
Example
const cat = { id: 1, type: 'cat', name: 'Fluffy' };
const catWithoutType = slice(cat, ['name', 'id']);
// catWithoutType will be:
// {id: 1, name: 'Fluffy'};
Example
// Usage with RxState
// Usage with RxState
export class AnimalsListComponent {
constructor(private state: RxState<ComponentState>, private api: ApiService) {
state.connect(
'animals'
this.api.getAnimals(),
(state, animals) => {
return animals.map(animal => slice(animal, ['id', 'name']));
}
);
}
}
Edge cases
slice(nonObject, 'prop' as any) > undefined;
slice(null as any, 'prop') > undefined;
slice(null as any, null as any) > undefined;
slice([state], 'concat') > undefined;
slice(state, 'nonExisting' as any) > undefined;
slice(state, null as any) > undefined;
slice(state, ['stateProp1', 'nonExistingProp']) >
{ stateProp1: stateProp1Value };
Signature
function slice<T extends object, K extends keyof T>(
object: T,
keys: K | K[]
): Pick<T, K>;