Conversion from both keys and values of object

Question

I have two sets of string values that I want to map from one to the other as a constant object. I want to generate two types from that map: 

• Keys and 
• Values

const KeyToVal = {
    MyKey1: 'myValue1',
    MyKey2: 'myValue2',
};

The keys are working well

type Keys = keyof typeof KeyToVal;

But I am having trouble with the compile-time type for values.

All of these converted my Values to string. I also tried referring How to infer typed mapValues using lookups in typescript?, but I either got my adaptations wrong, or the answers didn't fit my problem. 

Answer 1

You could just change the declaration of KeyToVal like this:

const KeyToVal = {
    MyKey1: 'myValue1',
    MyKey2: 'myValue2',
} as const; // <----- add the <as const> here

Then you can create the key types:

type Keys = keyof typeof KeyToVal;

Now you can create the types of values:

type ValuesTypes = typeof KeyToVal[Keys];