src/vs/editor/common/core/range.ts/Range/isIRange
class Range:	public static isIRange(obj: any): obj is IRange {
		return (
			obj
			&& (typeof obj.startLineNumber === 'number')
			&& (typeof obj.startColumn === 'number')
			&& (typeof obj.endLineNumber === 'number')
			&& (typeof obj.endColumn === 'number')
		);
	}