CreateObject function call implies correct return type

[markwpearce]

Previously, everything returned from createObject was ObjectType

Now, it looks at the arguments, and if passed string literals, it is able to infer either the built-in Component/Object or a custom component:

dateTime = createObject("roDatetime") ' this is the InterfaceType `roDateTime`
dateTime.getHours() ' this is an integer


button = createObject("roSgnode", "Poster") '  this is the ComponentType `roSgNodePoster`
button.uri ' this is a string

if the args are not string literals, it still just returns ObjectType....

function getObject(objectName as string)
    return createObject(objectName) ' this is just ObjectType
end function

[TwitchBronBron]

I'm not crazy about using a callback function on the TypedFunctionType class. Makes it harder to evaluate/inspect/reason about the type. And once this signature is there, it's going to be a breaking change to remove it if we need to redesign this feature/functionality in the future.

I'd much rather see proper overloading support implemented like they do in typescript, along with string literal value types. Something like this:

function createObject("roSGNode", "Label") as roSGNodeLabel
function createObject("roSGNode", "Rectangle") as roSGNodeRectangle

These would be auto-injected into the program when we define all the built-in types, and then we'd augment that list with the user-defined objects.

[markwpearce]

Ok. Hmmm. I don’t know about making support for overloading functions yet, so maybe I’ll change this so it’s just a special case, and does not change the interface/constructors for anything yet.

[TwitchBronBron]

The latest changes feel much better, protects us a bit from breaking changes. Thanks!