export default function extractLastExtensionOfFileName(compoundParameter: Readonly<{
    targetPath: string;
    withLeadingDot: boolean;
}>): string | null;
export default function extractLastExtensionOfFileName(compoundParameter: Readonly<{
    targetPath: string;
    withLeadingDot: boolean;
    mustThrowErrorIfLastPathSegmentHasNotDots: true;
}>): string;