src/vs/editor/common/model/bracketPairsTextModelPart/bracketPairsTree/length.ts/lengthDiff
export function lengthDiff(startLineCount: number, startColumnCount: number, endLineCount: number, endColumnCount: number): Length {
	return (startLineCount !== endLineCount)
		? toLength(endLineCount - startLineCount, endColumnCount)
		: toLength(0, endColumnCount - startColumnCount);
}