Improve overall typing of openlayers

At the moment I am looking into how to improve the typing of openlayers to improve a) typechecking (also in dependent projects) and b) generation of typescript typings.

Options

One huge issue that I have with the typing of openlayers are the Options objects of the layers. They all have a certain amount of strictly typed properties and can also accept arbitrary properties that get passed to the BaseObject. For typing purposes this bad.

What I would like to see is that all Options objects would get a property properties which would get passed to the BaseObject. I would like to look into this if you like the idea. This would be a breaking change and would only get included in v7. This mainly would affect the api of the layer types.

Nevertheless I found a way to type this properly in JSDoc, namely using

* @param {Options & Object<string, *>} opt_options Options.

Here is a PR for this: https://github.com/openlayers/openlayers/pull/11959

BaseObject

Maybe it is possible to incorporate @template Variables for the properties ( https://github.com/openlayers/openlayers/issues/11572 ).

Generic source types for layers

I created a PR for improved generic source types of layers here: https://github.com/openlayers/openlayers/pull/11948 The Layer and BaseVectorLayer were already using it but all other types are missing it. This mainly improves the types of getSource and setSource, but also improves assignability. For example assignig an ImageLayer to a variable of a type Layer<ImageSource>.

I will continue to gather some issues here.

[tschaub]

Another idea is to get rid of BaseObject altogether. I would be in favor of doing this in a v7.

[simonseyock]

FYI: I created https://github.com/simonseyock/jsdoc-type-pratt-parser and will see what the folks at jsdoc think about it: https://github.com/jsdoc/jsdoc/issues/1917