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Rest Parameters

Rest parameters allow an indefinite number of final arguments, and brings them into the function body as an array. They're denoted by three dots (...) before the parameter name.

function gatherParty(partyName: string, ...adventurers: string[]): string {
  return `${partyName} consists of: ${adventurers.join(", ")}`;
}

const msg = gatherParty("The Fellowship", "Frodo", "Sam", "Gandalf");
console.log(msg);
// "The Fellowship consists of: Frodo, Sam, Gandalf"

Don't confuse rest parameters with the similar but different spread syntax.

You've used rest parameters before, maybe without even realizing! console.log accepts rest parameters.

Assignment

Run the code as-is to see the tsc error. Take a look at main_test.ts: notice that sometimes it's called with different numbers of "labels" parameters
Fix the formatLabels function signature to accept a variable number of "labels" using rest parameters
Complete the formatLabels function, it should:
- Return the string "No Labels" if there are no labels
- Return the string "Label: LABEL" if there is only one label (where LABEL is the first label)
- Return the string "Labels: LABEL, LABEL" if there are multiple labels (LABEL is each label separated by a comma and a space)