Remove `maybeT` in favour of `dioptional` about tomland HOT 10 CLOSED

What is dioptional?
Link points to

lastT :: (Key -> BiToml a) -> Key -> BiToml (Last a)
lastT = Toml.wrapper . Toml.maybeT

the function uses maybeT self.

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@willbasky Sorry, link is wrong. It should be with commit. Look at dimaybeT. This function should convert BiCodec a to BiCodec (Maybe a)

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This function should convert BiCodec a to BiCodec (Maybe a)

Do you mean TomlCodec a -> TomlCodec (Maybe a)?
as it is in maybeT :: forall a . (Key -> TomlCodec a) -> Key -> TomlCodec (Maybe a)

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And why change maybeT with dimaybeT?

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Do you mean TomlCodec a -> TomlCodec (Maybe a)?

No, this function should be general and work for BiCodec

And why change maybeT with dimaybeT?

maybeT is wrong an it often happens that maybeT doesn't work as expected. So maybeT should be removed. So I want to have something like optional for Alternative for our our Codec. Unfortunately, optional for Codec works in the following way:

optional :: Codec r w a b -> Codec r w a (Maybe b)`

while I want:

dioptional :: Codec r w a b -> Codec r w (Maybe a) (Maybe b)

If you can write dioptional for Codec instead of BiCodec, it would be even better 👍

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How does it possible, on Hackage and on Github?

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type TomlCodec a = BiCodec Env St a is the same with type BiToml a = Bi Env St a?

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@willbasky Yeah, types were renamed in some recent PR. And the new version is not on Hackage yet.

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Does dimaybeT something like workaround now?

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Yes, it is. After dioptional is implemented in tomland, it will replace dimaybeT in summoner

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