 | ListLike-1.0.0: Generic support for list-like structures | Contents | Index |
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| Data.ListLike.FoldableLL | | Portability | portable | | Stability | provisional | | Maintainer | John Goerzen <jgoerzen@complete.org> |
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| Description |
Generic tools for data structures that can be folded.
Written by John Goerzen, jgoerzen@complete.org
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| Synopsis |
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| class FoldableLL full item | full -> item where | | foldl :: (a -> item -> a) -> a -> full -> a | | foldl' :: (a -> item -> a) -> a -> full -> a | | foldl1 :: (item -> item -> item) -> full -> item | | foldr :: (item -> b -> b) -> b -> full -> b | | foldr' :: (item -> b -> b) -> b -> full -> b | | foldr1 :: (item -> item -> item) -> full -> item |
| | | fold :: (FoldableLL full item, Monoid item) => full -> item | | | foldMap :: (FoldableLL full item, Monoid m) => (item -> m) -> full -> m |
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| FoldableLL Class
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| class FoldableLL full item | full -> item where |
This is the primary class for structures that are to be considered
foldable. A minimum complete definition provides foldl and foldr.
Instances of FoldableLL can be folded, and can be many and varied.
These functions are used heavily in Data.ListLike.
| | | Methods | | foldl :: (a -> item -> a) -> a -> full -> a | | Left-associative fold
| | | foldl' :: (a -> item -> a) -> a -> full -> a | | Strict version of foldl.
| | | foldl1 :: (item -> item -> item) -> full -> item | | A variant of foldl with no base case. Requires at least 1
list element.
| | | foldr :: (item -> b -> b) -> b -> full -> b | | Right-associative fold
| | | foldr' :: (item -> b -> b) -> b -> full -> b | | Strict version of foldr
| | | foldr1 :: (item -> item -> item) -> full -> item | | Like foldr, but with no starting value
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| |  Instances | |
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| Utilities
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| fold :: (FoldableLL full item, Monoid item) => full -> item |
| Combine the elements of a structure using a monoid.
fold = foldMap id
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| foldMap :: (FoldableLL full item, Monoid m) => (item -> m) -> full -> m |
| Map each element to a monoid, then combine the results
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| Produced by Haddock version 0.8 |