Ix

haskell98-1.1.0.1: Compatibility with Haskell 98

Ix

Synopsis

- class Ord a => Ix a where
  - range :: (a, a) -> [a]
  - index :: (a, a) -> a -> Int
  - inRange :: (a, a) -> a -> Bool
  - rangeSize :: (a, a) -> Int
- rangeSize :: Ix a => (a, a) -> Int

# Documentation

class Ord a => Ix a where Source

The `Ix` class is used to map a contiguous subrange of values in a type onto integers. It is used primarily for array indexing (see the array package).

The first argument `(l,u)` of each of these operations is a pair specifying the lower and upper bounds of a contiguous subrange of values.

An implementation is entitled to assume the following laws about these operations:

- ``inRange` (l,u) i == `elem` i (`range` (l,u))` ``
- ``range` (l,u) `!!` `index` (l,u) i == i`, when ``inRange` (l,u) i`
- ``map` (`index` (l,u)) (`range` (l,u))) == [0..`rangeSize` (l,u)-1]` ``
- ``rangeSize` (l,u) == `length` (`range` (l,u))` ``

Minimal complete instance: `range`, `index` and `inRange`.

Methods

range :: (a, a) -> [a]Source

The list of values in the subrange defined by a bounding pair.

index :: (a, a) -> a -> Int Source

The position of a subscript in the subrange.

inRange :: (a, a) -> a -> Bool Source

Returns `True` the given subscript lies in the range defined the bounding pair.

rangeSize :: (a, a) -> Int Source

The size of the subrange defined by a bounding pair.

Instances

Ix Bool |
Ix Char |
Ix Int |
Ix Integer |
Ix Ordering |
Ix () |
Ix GeneralCategory |
Ix SeekMode |
Ix IOMode |
Ix Month |
Ix Day |
(Ix a, Ix b) => Ix (a, b) |
(Ix a1, Ix a2, Ix a3) => Ix (a1, a2, a3) |
(Ix a1, Ix a2, Ix a3, Ix a4) => Ix (a1, a2, a3, a4) |
(Ix a1, Ix a2, Ix a3, Ix a4, Ix a5) => Ix (a1, a2, a3, a4, a5) |

rangeSize :: Ix a => (a, a) -> Int Source

The size of the subrange defined by a bounding pair.