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Tuples that are not restricted to two elements.

Here is an example of a 3-tuple:

> tuple = tuple3 1 "2" 3.0
> tuple
(Tuple 1 (Tuple "2" (Tuple 3.0 unit)))

Notice that a tuple is a nested structure not unlike a list. The type of tuple is this:

> :t tuple
Tuple Int (Tuple String (Tuple Number Unit))

That, however, can be abbreviated with the Tuple3 type:

Tuple3 Int String Number

All tuple functions are numbered from 1 to 10. That is, there's a get1 and a get10.

The getN functions accept tuples of length N or greater:

get1 tuple = 1
get3 tuple = 3
get4 tuple -- type error. `get4` requires a longer tuple. 

The same is true of the overN functions:

over2 negate (tuple3 1 2 3) = tuple3 1 (-2) 3

uncurryN can be used to convert a function that takes N arguments to one that takes an N-tuple:

uncurry2 (+) (tuple2 1 2) = 3

The reverse curryN function converts functions that take N-tuples (which are rare) to functions that take N arguments.

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In addition to types like Tuple3, there are also types like T3. Whereas Tuple3 describes a tuple with exactly three elements, T3 describes a tuple of length two or longer. More specifically, T3 requires two element plus a "tail" that may be unit or more tuple elements. Use types like T3 when you want to create a set of functions for arbitrary tuples. See the source for how that's done.