Tuples are another way of storing multiple values in a single value. They have a fixed number of elements (immutable), and so you can't cons to a tuple. Elements of a tuple do not need to be all of the same type!
var tuples = require('fantasy-tuples'), Tuple2 = tuples.Tuple2; Tuple2(1, 2)._1; // 1
Currently Fantasy Check is using Istanbul for code coverage analysis; you can run the coverage via the following command:
This assumes that you have istanbul installed correctly.
istanbul cover nodeunit -- test/*.js