belega

belega

Effective Haskell: Error in addPeano function (p 92, pdf)

The addPeano function switches the arguments in the recursive call. The implementation should be:

addPeano Z b = b
addPeano (S a) b = addPeano a (S b)
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RebeccaSkinner

RebeccaSkinner

Author of Effective Haskell

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