Copyright | (c) The University of Glasgow 2001-2009 |
---|---|
License | BSD-style (see the file libraries/base/LICENSE) |
Maintainer | libraries@haskell.org |
Stability | experimental |
Portability | portable |
Safe Haskell | Safe |
Language | Haskell2010 |
Sequential strategies provide ways to compositionally specify the degree of evaluation of a data type between the extremes of no evaluation and full evaluation. Sequential strategies may be viewed as complimentary to the parallel ones (see module Control.Parallel.Strategies).
- type Strategy a = a -> ()
- using :: a -> Strategy a -> a
- withStrategy :: Strategy a -> a -> a
- r0 :: Strategy a
- rseq :: Strategy a
- rdeepseq :: NFData a => Strategy a
- seqList :: Strategy a -> Strategy [a]
- seqListN :: Int -> Strategy a -> Strategy [a]
- seqListNth :: Int -> Strategy a -> Strategy [a]
- seqFoldable :: Foldable t => Strategy a -> Strategy (t a)
- seqMap :: Strategy k -> Strategy v -> Strategy (Map k v)
- seqArray :: Ix i => Strategy a -> Strategy (Array i a)
- seqArrayBounds :: Ix i => Strategy i -> Strategy (Array i a)
- seqTuple2 :: Strategy a -> Strategy b -> Strategy (a, b)
- seqTuple3 :: Strategy a -> Strategy b -> Strategy c -> Strategy (a, b, c)
- seqTuple4 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy (a, b, c, d)
- seqTuple5 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy (a, b, c, d, e)
- seqTuple6 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy (a, b, c, d, e, f)
- seqTuple7 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy g -> Strategy (a, b, c, d, e, f, g)
- seqTuple8 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy g -> Strategy h -> Strategy (a, b, c, d, e, f, g, h)
- seqTuple9 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy g -> Strategy h -> Strategy i -> Strategy (a, b, c, d, e, f, g, h, i)
The sequential strategy type
type Strategy a = a -> () Source
The type
is Strategy
aa -> ()
.
Thus, a strategy is a function whose sole purpose it is to evaluate
its argument (either in full or in part).
Application of sequential strategies
withStrategy :: Strategy a -> a -> a Source
Evaluate a value using the given strategy.
This is simply using
with arguments reversed.
Basic sequential strategies
rdeepseq :: NFData a => Strategy a Source
rdeepseq
fully evaluates its argument.
Relies on class NFData
from module Control.DeepSeq.
Sequential strategies for lists
seqList :: Strategy a -> Strategy [a] Source
Evaluate each element of a list according to the given strategy.
This function is a specialisation of seqFoldable
to lists.
seqListN :: Int -> Strategy a -> Strategy [a] Source
Evaluate the first n elements of a list according to the given strategy.
seqListNth :: Int -> Strategy a -> Strategy [a] Source
Evaluate the nth element of a list (if there is such) according to the given strategy. The spine of the list up to the nth element is evaluated as a side effect.
Sequential strategies for foldable data types
seqFoldable :: Foldable t => Strategy a -> Strategy (t a) Source
Evaluate the elements of a foldable data structure according to the given strategy.
seqMap :: Strategy k -> Strategy v -> Strategy (Map k v) Source
Evaluate the keys and values of a map according to the given strategies.
seqArray :: Ix i => Strategy a -> Strategy (Array i a) Source
Evaluate the elements of an array according to the given strategy. Evaluation of the array bounds may be triggered as a side effect.
seqArrayBounds :: Ix i => Strategy i -> Strategy (Array i a) Source
Evaluate the bounds of an array according to the given strategy.
Sequential strategies for tuples
Evaluate the components of a tuple according to the given strategies. No guarantee is given as to the order of evaluation.
seqTuple5 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy (a, b, c, d, e) Source
seqTuple6 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy (a, b, c, d, e, f) Source
seqTuple7 :: Strategy a -> Strategy b -> Strategy c -> Strategy d -> Strategy e -> Strategy f -> Strategy g -> Strategy (a, b, c, d, e, f, g) Source