src/vs/editor/browser/controller/textAreaState.ts/TextAreaState/constructor
class TextAreaState:	constructor(
		public readonly value: string,
		/** the offset where selection starts inside `value` */
		public readonly selectionStart: number,
		/** the offset where selection ends inside `value` */
		public readonly selectionEnd: number,
		/** the editor range in the view coordinate system that matches the selection inside `value` */
		public readonly selection: Range | null,
		/** the visible line count (wrapped, not necessarily matching \n characters) for the text in `value` before `selectionStart` */
		public readonly newlineCountBeforeSelection: number | undefined,
	) { }