cf.completefrontend

Predict the typesEasy

What does TypeScript infer for T in each of these calls?

Name the type each ^? line points at, and every error TypeScript reports.

What does TypeScript report here?
function identity<T>(value: T): T {  return value;}function pair<T>(first: T, second: T): [T, T] {  return [first, second];} const one = identity("hello");//    ^?let two = identity("hello");//  ^?const three = identity<string | number>(42);//    ^?const four = pair(1, 2);//    ^?const five = pair(1, "two");

Work it out first: the compiler shows every error and type.

The answer

Work out every error TypeScript reports and every type it shows, line by line. Then check.

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