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Is it possible to use enum's values as value for object key in type declaration?


I have enum HealthPlanStatus which was generated by enum HealthPlanStatus. In the end I would like to use enum's keys and values to generate not only status keys for type IHealthPlanResponse but also a title value as enum's values.

export enum HealthPlanStatus {
    Todo = 'To-Do',
    InProgress = 'Working on it',
}
export type IHealthPlanResponse = {
    [status in keyof typeof HealthPlanStatus]: {
        title: string;
    };
};

It gives me strict structure where I have a status key as enum's key (Todo, InProgress...):

type IHealthPlanResponse = {
    readonly Todo: {
        title: string;
    };
    readonly InProgress: {
        title: string;
    };
}

Also I would like to have a title type as enum's values. For example:

 type IHealthPlanResponse = {
    readonly Todo: {
        title: 'To-Do';
    };
    readonly InProgress: {
        title: 'Working on it';
    };
}

Solution

  • Does this work for you?

    export enum HealthPlanStatus {
        Todo = 'To-Do',
        InProgress = 'Working on it',
    }
    export type IHealthPlanResponse = {
        readonly [status in keyof typeof HealthPlanStatus]: {
            title: (typeof HealthPlanStatus)[status];
        };
    };
    
    let t: IHealthPlanResponse = {} as any
    const status = t.InProgress.title   // -> HealthPlanStatus.InProgress
    

    If you don't like to see the enum 'key' here and want to have the string literal as a type you can change it to this:

    export type IHealthPlanResponse = {
        readonly [status in keyof typeof HealthPlanStatus]: {
            title: `${(typeof HealthPlanStatus)[status]}`;
        };
    };
    
    let t: IHealthPlanResponse = {} as any
    const status = t.InProgress.title   // -> 'Working on it'