# The Other Prelude

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Uchchwhash (Talk | contribs) (fmt, outline) |
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== Naming Conventions == |
== Naming Conventions == |
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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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+ | |||

+ | |||

+ | -- should the Functor hierarchy proposal be adopted? |
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+ | 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 |
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+ | return :: a -> m a |
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+ | fail :: String -> m a |
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+ | |||

</haskell> |
</haskell> |
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## 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 andfst. They go to the Extension module.snd

## 4 Issues

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

## 5 The Hierarchy

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

## 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

- Mathematical prelude discussion - A numeric Prelude. Could this be merged into this one?
- Prelude extensions and Prelude function suggestions - Unlike "The Other Prelude" they
*enhance*the Prelude.