Recap: Generic Functions

Part of the Introduction To Luau section of Coddy's Lua journey. Lesson 62 of 73.

Challenge

Medium

Combine generic aliases and generic functions in one program.

Define a generic type alias named Pair with two type parameters T and U, describing a table with:

first of type T
second of type U

Create a generic function named makePair that declares T and U, accepts first: T and second: U, and returns them packed into a Pair<T, U>.

Create a generic function named describePair that declares T and U, accepts a pair: Pair<T, U>, and returns the string ({first}, {second}) built with string interpolation (return type string).

Then:

create playerScore of type Pair<string, number> by calling makePair("<code>Nova", 87)
create levelDone of type Pair<number, boolean> by calling makePair(3, true)
print playerScore.first
print playerScore.second
print describePair(playerScore)
print describePair(levelDone)
print describePair(makePair("Luau", 2026)) in a single line

Try it yourself

-- Write code here
-- 1) define type Pair<T, U> = {first: T, second: U}
-- 2) define makePair<T, U>(first: T, second: U): Pair<T, U>
-- 3) define describePair<T, U>(pair: Pair<T, U>): string
--    returning `({pair.first}, {pair.second})`
-- 4) build playerScore (the exact text from the instructions, 87) and levelDone (3, true),
--    then print the five required lines

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