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The Other Prelude

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== Naming Conventions ==
== Naming Conventions ==
The principal is to make the names very readable for both beginners and category theorists (if any).
The principal is to make the names very readable for both beginners and category theorists (if any).
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 +
== Guidelines ==
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* The prelude should not contain any "projection" functions (like <hask>fst</hask> and <hask>snd</hask>. They go to the Extension module.
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== Issues ==
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* Should alphanumeric names be preferred over symbols when defining a class?
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== The Hierarchy ==
== The Hierarchy ==
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<haskell>
<haskell>
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import Prelude () -- hide everything
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 +
-- the idea is to remove 'fmap'
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-- and map :: (a -> b) -> [a] -> [b] to be a special case
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 +
class Functor f where
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map :: (a -> b) -> f a -> f b
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 +
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-- should the Functor hierarchy proposal be adopted?
 +
class Monad m where
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(>>=) :: m a -> (a -> m b) -> m b
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(>>) :: m a -> m b -> m b
 +
return :: a -> m a
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fail :: String -> m a
 +
</haskell>
</haskell>

Revision as of 06:29, 21 December 2006

Contents

1 Call for Contribution

This fun project, called "The Other Prelude", and is a creative reconstruction of the standard Prelude. By disregarding history and compatibility, we get a clean sheet.

2 Naming Conventions

The principal is to make the names very readable for both beginners and category theorists (if any).

3 Guidelines

  • The prelude should not contain any "projection" functions (like
    fst
    and
    snd
    . They go to the Extension module.


4 Issues

  • Should alphanumeric names be preferred over symbols when defining a class?


5 The Hierarchy

  • TheOtherPrelude
    - Minimalistic module.
  • TheOtherPrelude.Extension
    - Convenient definitions.

6 The Code

Currently, the code is in Wiki form. If people do agree that the collaborative decisions begot something pretty, we'll have a group of files in darcs.haskell.org some time.

The imaginery Prelude as it stands, 

import Prelude ()    -- hide everything
 
-- the idea is to remove 'fmap' 
-- and map :: (a -> b) -> [a] -> [b] to be a special case
 
class Functor f where
  map :: (a -> b) -> f a -> f b
 
 
-- should the Functor hierarchy proposal be adopted?
class Monad m where
  (>>=) :: m a -> (a -> m b) -> m b
  (>>) :: m a -> m b -> m b
  return :: a -> m a
  fail :: String -> m a

How to use it, as it stands, 

import Prelude ()                            -- hide everything
import TheOtherPrelude                       -- get everything
import qualified TheOtherPrelude.Monad as M  -- standard convention

7 See Also

Retrieved from "http://www.haskell.org/haskellwiki/The_Other_Prelude"

Categories: Mathematics | Code