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Gü?nther Schmidt

8 Mar 2009 8 Mar '09

10:30 a.m.

Hi, I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it. I tried to understand the respective user manuals but it's still all Greek to me. Someone please help! Günther

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Sterling Clover

8 Mar 8 Mar

1:36 p.m.

You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice. Cheers, S. On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

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G?uenther Schmidt

2:58 p.m.

Hi Sterling, sry, but I can't get it to work. Günther Sterling Clover schrieb:

You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice.

Cheers, S.

On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt mailto:gue.schmidt@web.de> wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

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Alexander Dunlap

3:31 p.m.

What problems are you encountering? Alex On Sun, Mar 8, 2009 at 11:58 AM, G?uenther Schmidt wrote:

Hi Sterling,

sry, but I can't get it to work.

Günther

Sterling Clover schrieb:

...
You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice.

Cheers, S.

On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt mailto:gue.schmidt@web.de> wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org mailto:Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

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Gü?nther Schmidt

3:40 p.m.

Hi Alexander, well I have this: newtype AdmissionDate = AdmDt LocalTime deriving (Data,Typeable ..) at least that's where I wonna get. I don't know how to create the proper instance declarations though for LocalTime. AdmissionDate is an element of a larger data structure, this data structure for instance also has a newtype DischargeDate = DchrgDt LocalTime deriving (Data,Typeable ...) With my haskell work so far I was blessedly free of the need for deriving. Until now ... Günther Alexander Dunlap schrieb:

What problems are you encountering?

Alex

On Sun, Mar 8, 2009 at 11:58 AM, G?uenther Schmidt wrote:

...
Hi Sterling,

sry, but I can't get it to work.

Günther

Sterling Clover schrieb:

...
You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice.

Cheers, S.

On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt mailto:gue.schmidt@web.de> wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org mailto:Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

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Alexander Dunlap

3:42 p.m.

Well you can do

deriving instance Typeable LocalType

etc. if you enable the DeriveDataTypeable and StandaloneDeriving extensions. You will get other error messages for missing instances; just keep adding

deriving instance Typeable Day

etc. Eventually, you will need to implement an instance by hand for Pico, because Pico's data constructors are not exported from Data.Fixed. I'm not very familiar with Data and Typeable so I can't help you there, but you can probably look at some existing instances for help. Hope that's useful for you. Alex On Sun, Mar 8, 2009 at 12:40 PM, Gü?nther Schmidt wrote:

Hi Alexander,

well I have this:

newtype AdmissionDate = AdmDt LocalTime deriving (Data,Typeable ..)

at least that's where I wonna get.

I don't know how to create the proper instance declarations though for LocalTime.

AdmissionDate is an element of a larger data structure, this data structure for instance also has a

newtype DischargeDate = DchrgDt LocalTime deriving (Data,Typeable ...)

With my haskell work so far I was blessedly free of the need for deriving. Until now ...

Günther

Alexander Dunlap schrieb:

...
What problems are you encountering?

Alex

On Sun, Mar 8, 2009 at 11:58 AM, G?uenther Schmidt wrote:

...
Hi Sterling,

sry, but I can't get it to work.

Günther

Sterling Clover schrieb:

...
You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice.

Cheers, S.

On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt mailto:gue.schmidt@web.de> wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org mailto:Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

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Gü?nther Schmidt

4:18 p.m.

Hi Alexander, this does the trick! Günther Alexander Dunlap schrieb:

Well you can do

...
deriving instance Typeable LocalType

etc. if you enable the DeriveDataTypeable and StandaloneDeriving extensions. You will get other error messages for missing instances; just keep adding

...
deriving instance Typeable Day

etc. Eventually, you will need to implement an instance by hand for Pico, because Pico's data constructors are not exported from Data.Fixed. I'm not very familiar with Data and Typeable so I can't help you there, but you can probably look at some existing instances for help.

Hope that's useful for you.

Alex

On Sun, Mar 8, 2009 at 12:40 PM, Gü?nther Schmidt wrote:

...
Hi Alexander,

well I have this:

newtype AdmissionDate = AdmDt LocalTime deriving (Data,Typeable ..)

at least that's where I wonna get.

I don't know how to create the proper instance declarations though for LocalTime.

AdmissionDate is an element of a larger data structure, this data structure for instance also has a

newtype DischargeDate = DchrgDt LocalTime deriving (Data,Typeable ...)

With my haskell work so far I was blessedly free of the need for deriving.. Until now ...

Günther

Alexander Dunlap schrieb:

...
What problems are you encountering?

Alex

On Sun, Mar 8, 2009 at 11:58 AM, G?uenther Schmidt wrote:

...
Hi Sterling,

sry, but I can't get it to work.

Günther

Sterling Clover schrieb:

...
You shouldn't need any extra tools for this. A combination of the StandaloneDeriving and DeriveDataTypeable extensions in GHC should suffice.

Cheers, S.

On Sun, Mar 8, 2009 at 10:30 AM, Gü?nther Schmidt mailto:gue.schmidt@web.de> wrote:

Hi,

I need to derive Data, Typeable for Data.Time.LocalTime. I had hoped to use either derive or DrIFT to generate the instance declarations for it.

I tried to understand the respective user manuals but it's still all Greek to me.

Someone please help!

Günther

_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org mailto:Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

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Alexander Dunlap
G?uenther Schmidt
Gü?nther Schmidt
Sterling Clover