for more information visit the package's GitHub page
Package contains the following modules:
An array that always contains at least one element.
Additionaly, it can track a currently selected index, which is guaranteed to point to an existing element in the array.
These additional constraints enable two functions, namely getFirst
and
getSelected
to return a value directly instead of a Maybe
.
Inspired by mgold/elm-nonempty-list.
import Array.NonEmpty as NEA exposing (NonEmptyArray)
oneElement : NonEmptyArray
oneElement = NEA.fromElement 13
twoElements : NonEmptyArray
twoElements = NEA.push 42 one
createdFromList : Maybe NonEmptyArray
createdFromList = NEA.fromList ["a", "b", "b"]
All functions from core Array
are available, with the exception of isEmpty
(which would be an alias for False
).
In addition, non-empty-array offers additional functions made possible due to the additional constraints:
getFirst
: Returns the first element. Since it is known that this element exists, this function does not return a Maybe but the actual element type.getSelected
: Returns the element at the currently selected index. Since it is known that this element exists, this function does not return a Maybe but the actual element type.updateSelected
: Updates the element at the currently selected index.Finally, it offers update
, removeAt
and removeAtSafe
, which are not in core Array
but inspired by Array.Extra
.
The easiest way to run the tests is to install the npm packages elm-test
and elm-verify-examples
globally:
npm i elm-test -g
npm i elm-verify-examples -g
Then, from the project root directory, run
elm-verify-examples && elm-test
This will require downloading some packages on the first run.
This library uses the BSD3 License. See LICENSE for more information.