# Type arithmetic

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However, many other representations of numbers are possible, including binary and balanced base three. Type arithmetic may also include type representations of boolean values and so on. | However, many other representations of numbers are possible, including binary and balanced base three. Type arithmetic may also include type representations of boolean values and so on. | ||

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+ | [[Category:Idioms]] |

## Revision as of 20:48, 1 February 2006

**Type arithmetic** is calculations on types using fundeps as functions.

A simple example is Peano numbers:

data Zero

data Succ a

class Add a b ab | a b -> ab, a ab -> b instance Add Zero b b instance (Add a b ab) => Add (Succ a) b (Succ ab)

However, many other representations of numbers are possible, including binary and balanced base three. Type arithmetic may also include type representations of boolean values and so on.