haskell - Generating a Truth Table

Question

If I have some values A B C, is is possible to generate a list of all their possible truth values: the input is ["X", "Y", "Z"] e.g. the list contains 8 lists (rows of table)

[ [ ("X",True), ("Y",True), ("Z", True) ],
[ ("X",True), ("Y",True), ("Z", False) ],.... ]

Are there any hints on how to do this?

I would like to generate a truth table for an arbitrary number of variables.

Answer 1

What you need is not a truth table but rather a cartesian product. You can obtain what you want using list comprehension: [(x,y,z) | x <- [True, False], y <- [True,False], z <- [True,False]]

If you want to keep variable names you can use tuples: [(x,y,z) | x <- [("X", True), ("X", False)], y <- [("Y", True), ("Y", False)], z <- [("Z", True),("Z", False)]]