API Ideas

[evancz]

This is for organization. Open a separate issue for your particular idea.

This is a collection of API ideas that have sprouted up as folks have used core. It is not an invitation to do a free for all of changes. I am just collecting the most promising ideas in one place so that we can assess them all together in a coherent way.

Primitives

• #417 - bindings to Number.toFixed
• #657 - rename toString
• #593 - add Never -> a function

Data Structures

• #408 - add List.singleton
• #317 - have Dict.keys return a Set
• https://github.com/elm-lang/elm-compiler/issues/646 - add Array.remove
• #298 - add Array.update
• #366 - negative indexes in Array.get and Array.set
• #699 - make Array.slice 3 0 take until the end of the array
• https://github.com/elm-community/maybe-extra/pull/5 - super interesting discussion of naming
• #776 - flip arguments of List.append

Maybe and Result

• #720 - rename Result.formatError to Result.mapError to match Task.mapError
• #369 - clearly define the "use case" for Maybe and Result in APIs
• #164 - add Maybe.isNothing

Json

• #484 - Add Encode.dict

Tasks

• generate random numbers - #924
• Task.parallel - #223
• reorder args of andThen so backticks can be removed - thread
• add Time.utcOffset - https://github.com/elm-lang/elm-compiler/pull/705, #486
• move Process.sleep to Task.sleep - #693

[laszlopandy]

When thinking about what is in core, here is a good way to organize it:

Basic types	Containers	Graphics	Network	User interaction	Utils
Basics	Array	Color		Keyboard	Debug
Bitwise	List	Graphics.Element		Mouse	Json.Decode
Char	Set	Graphics.Collage		Touch	Json.Encode
Maybe	Dict	Graphics.Input		Window	Random
Result		Graphics.Input.Field			Time
Signal		Text			Date
Task		Transform2D			Regex
String					Trampoline

As you can see, there are no networking modules left in core. Http and Websocket were removed after 0.15, when their APIs were migrated to use Tasks instead of Signals. Organizing the classes like this in the documentation would make it much easier for developers to understand what is in core.