Re: Hi, I have a question!

[NamO]

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



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Hi, I have a question!

[NamO]

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.



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