src/vs/editor/common/textModelGuides.ts/IndentGuide/constructor
class IndentGuide:	constructor(
		public readonly visibleColumn: number | -1,
		public readonly column: number | -1,
		public readonly className: string,
		/**
		 * If set, this indent guide is a horizontal guide (no vertical part).
		 * It starts at visibleColumn and continues until endColumn.
		*/
		public readonly horizontalLine: IndentGuideHorizontalLine | null,
		/**
		 * If set (!= -1), only show this guide for wrapped lines that don't contain this model column, but are after it.
		*/
		public readonly forWrappedLinesAfterColumn: number | -1,
		public readonly forWrappedLinesBeforeOrAtColumn: number | -1
	) {
		if ((visibleColumn !== -1) === (column !== -1)) {
			throw new Error();
		}
	}