Beginners Digest, Vol 46, Issue 16

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Beginners Digest, Vol 46, Issue 17

if i compile the following code I get "bintree.hs:3:13: Not in scope: data > constructor `BinTree'" > > data BinTree a = Node BinTree a BinTree a | EmptyBinTree deriving Show > > b1 = (Node (BinTree 3) EmptyBinTree) > > please help > > -kak > > >

Beginners Digest, Vol 46, Issue 18

n it can't deduce "a" from the usage. -R. Kyle Murphy Sent from my phone. On Apr 13, 2012 1:03 PM, "Kak Dod" wrote: > Thanks Tom. this is what i wanted > I do not want "Node a" there, I wants only Node and Tom's solution works. > Thanks to all . > > -- > *From:* Tom Murphy > *To:* Kak Dod > *Cc:* Kyle Murphy ; "beginners@haskell.org" < > beginners@haskell.org> > *Sent:* Friday, 13 April 2012 4:53 PM > *Subject:* Re: [Haskell-beginners] error: Not in scope: data constructor > `BinTree' > > "(BinTree a)" needs to be in parentheses to pattern-match properly. > > data BinTree a = Node (BinTree a) (BinTree) a | EmptyBinTree > deriving Show > > On 4/13/12, Kak Dod wrote: > > Thank you but > > > > if I change the code like this: > > > > data BinTree a = Node BinTree a BinTree a | EmptyBinTree deriving Show > > > > b1 = Node 3 EmptyBinTreeEmptyBinTree > > > > Then I am get this error: > > > > bintree.hs:1:23: > > `BinTree' is not applied to enough type arguments > > Expected kind `?', but `BinTree' has kind `k0 -> *' > > In the type `BinTree' > > In the definition of data constructor `Node' > > In the data type declaration for `BinTree' > > Failed, modules loaded: none. > > > > > > > > > > > > From: Kyle Murphy > > To: Kak Dod > > Cc: "beginners@haskell.org" > > Sent: Friday, 13 April 2012 4:38 PM > > Subject: Re: [Haskell-beginners] error: Not in scope: data constructor > > `BinTree' > > > > > > Your constructor is called Node, not BinTree. > > data BinTree a = Node a (BinTree a) (BinTree a) | EmptyNode > > b1 = Node 3 EmptyNode EmptyNode > > -R. Kyle Murphy > > Sent from my phone. > > On Apr 13, 2012 12:24 PM, "Kak Dod" wrote: > > > > if i compile the following code I get "bintree.hs:3:13: Not in scope: > data > > constructor `BinTree'" > >> > >> > >> > >>data BinTree a = Node BinTree a BinTree a | EmptyBinTree deriving Show > >> > >>b1 = (Node (BinTree 3) EmptyBinTree) > >> > >> > >> > >>please help > >> > >> > >>-kak > >> > >> > >>___ > >>Beginners mailing list > >>Beginners@haskell.org > >>http://www.haskell.org/mailman/listinfo/beginners > >> > >> > > > -- next part -- An HTML attachment was scrubbed... URL: <http://www.haskell.org/pipermail/beginners/attachments/20120413/74418cca/attachment.htm> -- ___ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners End of Beginners Digest, Vol 46, Issue 18 *