Re: Hi, I have a question!
Derek Elkins [EMAIL PROTECTED] writes: Either use a different name for your operator, or specify the + that you want by writing OperationTest.+ instead of +. You can also hide the Prelude (+), though it is a somewhat useful function. Wouldn't making Nat an instance of Num also work? instance Num Nat where -- the definition of (+) for Nat here -kzm -- If I haven't seen further, it is by standing in the footprints of giants ___ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Hi, I have a question!
Mmmm. and then How can I solve this problem? Would you say the solution. Thank you. Ashley Yakeley [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] In article [EMAIL PROTECTED], NamO [EMAIL PROTECTED] wrote: But above source make an error like bellow Reading file g:\Haskell\OperationTest.hs: Dependency analysis ERROR g:\Haskell\OperationTest.hs:8 - Ambiguous variable occurrence + *** Could refer to: OperationTest.+ Prelude.+ There's already a definition for (+) imported from the Prelude. When you write Succ (m + n) the interpreter doesn't know whether you mean the one you've just defined (OperationTest.+) or the one imported from the Prelude (Prelude.+). -- Ashley Yakeley, Seattle WA ___ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Hi, I have a question!
In article [EMAIL PROTECTED], NamO [EMAIL PROTECTED] wrote: Mmmm. and then How can I solve this problem? Would you say the solution. Thank you. Either use a different name for your operator, or specify the + that you want by writing OperationTest.+ instead of +. -- Ashley Yakeley, Seattle WA ___ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
Hi, I have a question!
Hi. I am a student, who get interesting in Haskell. So, nowdays, I study Hakell with Introduction to Functional Programming using Haskell - second edition And today, I face an error from bellow code. module OperationTest where data Nat = Zero | Succ Nat deriving (Show) (+) :: Nat - Nat - Nat m + Zero = m m + Succ n = Succ (m + n) But above source make an error like bellow Reading file g:\Haskell\OperationTest.hs: Dependency analysis ERROR g:\Haskell\OperationTest.hs:8 - Ambiguous variable occurrence + *** Could refer to: OperationTest.+ Prelude.+ above source is from the text book - Introduction to Functional Programming using Haskell - second edition and I use Hugs to interpret it. I understand what interpreter say, but I don't know How I can solve this problem. Please, Help me!!! - 5 - P.S. Tank you very much to read my broken english letter. ___ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: Hi, I have a question!
In article [EMAIL PROTECTED], NamO [EMAIL PROTECTED] wrote: But above source make an error like bellow Reading file g:\Haskell\OperationTest.hs: Dependency analysis ERROR g:\Haskell\OperationTest.hs:8 - Ambiguous variable occurrence + *** Could refer to: OperationTest.+ Prelude.+ There's already a definition for (+) imported from the Prelude. When you write Succ (m + n) the interpreter doesn't know whether you mean the one you've just defined (OperationTest.+) or the one imported from the Prelude (Prelude.+). -- Ashley Yakeley, Seattle WA ___ Haskell-Cafe mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell-cafe
