The exclusivity requirement in TypeScript for generics

This example is presented purely for illustrative purposes and should not be considered a real-world scenario.

function myCustomFunc<A extends string, B extends string>(str1: A, str2: B): string {
  return "";
}

How can we ensure that A and B are distinct in order to prevent calling myCustomFunc with identical values like

myCustomFunc("Example", "Example")
?

Answer №1

I believe I have solved the problem.

function newFunction<T1 extends string, T2 extends string>(str1: T1, str2: T2 extends T1 ? never : T2): string {
  return "";
}

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