Difference between revisions of "Talk:Library for binary"

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(Fair question...)
 
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What's the difference between this and [http://www.haskell.org/ghc/docs/latest/html/libraries/base/Data-Bits.html Data.Bits]? -- [[User:EricKow|kowey]] 14:55, 7 March 2007 (UTC)
 
What's the difference between this and [http://www.haskell.org/ghc/docs/latest/html/libraries/base/Data-Bits.html Data.Bits]? -- [[User:EricKow|kowey]] 14:55, 7 March 2007 (UTC)
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<hask>Data.Bits</hask> provides bitwise operations on integers. This library represents a collection of bits explicitly, as a Haskell list. That means that all of Haskell's list processing functions are available to you. It's also means you can do things like
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<haskell>
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data Tree t = Leaf t | Branch (Tree t) (Tree t)
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get_node :: Bits -> Tree t -> Tree t
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get_node [] t = t
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get_node (b:bs) (Branch t0 t1) = get_node bs $ if b == Zero then t0 else t1
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</haskell>
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I don't see a way to do that (easily) with <hask>Data.Bits</hask>. (In particular, if you encode bits as a plain integer, how to you tell the difference between 0 and 000? With a list encoding, <hask>[Zero]</hask> and <hask>[Zero,Zero,Zero]</hask> are quite distinct.)
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In summary, you could say that this library is for solving a slightly different problem. [[User:MathematicalOrchid|MathematicalOrchid]] 15:53, 7 March 2007 (UTC)

Latest revision as of 15:53, 7 March 2007

What's the difference between this and Data.Bits? -- kowey 14:55, 7 March 2007 (UTC)

Data.Bits provides bitwise operations on integers. This library represents a collection of bits explicitly, as a Haskell list. That means that all of Haskell's list processing functions are available to you. It's also means you can do things like

data Tree t = Leaf t | Branch (Tree t) (Tree t)

get_node :: Bits -> Tree t -> Tree t
get_node [] t = t
get_node (b:bs) (Branch t0 t1) = get_node bs $ if b == Zero then t0 else t1

I don't see a way to do that (easily) with Data.Bits. (In particular, if you encode bits as a plain integer, how to you tell the difference between 0 and 000? With a list encoding, [Zero] and [Zero,Zero,Zero] are quite distinct.)

In summary, you could say that this library is for solving a slightly different problem. MathematicalOrchid 15:53, 7 March 2007 (UTC)