nesting

[barak]

*AutoDiff> let shouldBeOne = d (\x -> d (x*) 1) 1
*AutoDiff> shouldBeOne
0

[friedbrice]

Will look into

[barak]

Here is how the ad package handles it. And yes, the auto does sort of break the fourth wall of the implementation.

$ cabal install ad
$ ghci
Prelude> :m + Numeric.AD
Prelude Numeric.AD> let d = diff
Prelude Numeric.AD> d (\x -> d (auto x*) 1) 1
1