# Talk:Peano numbers

### From HaskellWiki

Theoretically speaking, the numbers defined here are not Peano numbers. As far as I know it is difficult, if not impossible, to define such inductive types in Haskell. In particular, *infinity* is included in this type (as *infinite lists* are included in the list type). (Sorry for my imprecise languages here.) People who are looking for formal, theoretical foundation should take this Wiki page with a pinch of salt. --Favonia 02:27, 30 May 2011 (UTC)