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Inferred Return Types

So you know how we discussed that:

const myPowerLevel = 9000;

Is better TypeScript than:

const myPowerLevel: number = 9000;

What follows is a bit of personal opinion, but I think the same is generally true for function return (not parameter) types.

Instead of this:

function divide(a: number, b: number): number {
  return a / b;
}

We can write this:

function divide(a: number, b: number) {
  return a / b;
}

And TypeScript infers the output type as number.

Why Are Inferred Return Types Better?

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Support.ai needs a way to combine our internal system prompt with a user's prompt.

Complete the combinePrompts function, it should:

Accept two string parameters: systemPrompt and userPrompt.
Return them concatenated together separated by a newline \n. The system prompt should come first, followed by the user prompt.

The return type should be inferred as a string. Not explicitly specified.