Rescript has only one way to access tuple elements: destructuring, this limitation prevents from using them as fixed length arrays
let ageAndName = (24, "Lil' ReScript")
// possible to get item by destructuring
let (_, name) = ageAndName
// NOT ALLOWED???
let name = ageAndName[2]
Access by index it’s type safe/sound when the compiler knows the length of the array, so index it’s limited to range {0,lenght-1} even typescript knows it
The generated tuple js is a plain array so, the only thing preventing {0,lenght-1} type safe random access is the language itself