| Safe Haskell | Safe-Infered |
|---|
Data.Natural
Description
Provides a type for natural numbers.
- data Natural
Documentation
The type of natural numbers.
Note that matching a natural number against a negative pattern might not work as you expect.
For example, evaluating the following expression results in a run-time error, instead of the
result "plus five":
case 5 :: Natural of
-5 -> "minus five"
5 -> "plus five"
The reason is that the == operator of Natural is used for checking if the patterns
match, making it necessary to convert -5 to Natural.