depth for generics is broken

[kuribas]

when using Generics, and incorrect depth is used:

> data Test = Test1 Int | Test2 String | Test3 String deriving (Generic, Show)
> instance Monad m => Serial m Test
> list 1 series :: [Test]
[Test1 0]
> list 2 series :: [Test]
[Test1 0,Test2 "",Test1 1,Test3 "",Test1 (-1)]

it looks like it's using the depth of the Rep Test, instead of the depth of Test.

[Bodigrim]

Could you please clarify what exactly is broken here?

[kuribas]

well, I would expect the different constructors to appear equally in the generated list, but that doesn't seem the case. For example Test1 1 comes before Test3 "".

[Bodigrim]

I don't think this has anything to do with Generic. This is just a consequence of instances for Int and String:

> listSeries 0 :: [Int]
[0]
> listSeries 0 :: [String]
[]
> listSeries 1 :: [Int]
[0,1,-1]
> listSeries 1 :: [String]
[""]

[kuribas]

Ah, indeed. Why do the instances for Int and String behave differently (one is empty at 0 level, the other not)?

[Bodigrim]

Because Int is considered to be a primitive type, but String is [Char], so you need to spend at least one unit of depth to get [].