range-set-list-0.1.1.0: README.md

# range-set-list

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A trivial implementation of range sets.

You can find the package (and it's documentation) on [hackage](http://hackage.haskell.org/package/range-set-list).

This module is intended to be imported qualified, to avoid name
clashes with Prelude functions, e.g.

```haskell
import Data.RangeSet.List (RSet)
import qualified Data.RangeSet.List as RSet
```

The implementation of `RSet` is based on _list_.

Compared to [`Data.Set`](http://hackage.haskell.org/package/containers-0.5.4.0/docs/Data-Set.html),
this module imposes also [`Enum`](http://hackage.haskell.org/package/base-4.6.0.1/docs/Prelude.html#t:Enum)
restriction for many functions.
We must be able to identify consecutive elements to be able to _glue_ and _split_ ranges properly.

The implementation assumes that

```haskell
x < succ x
pred x < x
```

and there aren't elements in between (not true for `Float` and `Double`).
Also `succ` and `pred` are never called for largest or smallest value respectively.