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A comment on The Derivative of a Number. Parent comment

Re:The Derivative of a Number by kvb on Tuesday August 19, 2014 @11:32PM (#8200978)
Great answer, but on a pedantic note, it's not quite true that the derivative of a data type is its zipper. The derivative is the one-hole context, but the zipper is more like a one-substructure context instead. There's a bit more elaboration here: [1].

[1] http://en.wikibooks.org/wiki/Haskell/Zippers

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Re:The Derivative of a Number by tel on Wednesday August 20, 2014 @06:04AM (#8201728)
True, I should have been more precise. The zipper just is a technique for using one-hole contexts to make a path as you drill through a recursive type.
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