Meaningful Object Keys in TypeScript

In Typescript, Record is a common way to express an object type. For example:

The disadvantage of using a Record in some cases is that you lose the benefit of expressing the meaning of the key. Let’s take the following example:

Looking at this code, I can’t know that the string type inside the memory Record refers to a Lambda’s id.

There are two possible solutions. The first is to use an index signature:

This approach has the advantage that you can choose the property’s name. Consequently, you are limited to using a string, number, or symbol as the type.

The second is to point to the Lambda id type directly:

Now I can understand the relationship in my schema more easily.

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