export default function getExpectedToBeSingleChildOfTemplateElement<DOM_ElementSubtype extends Element>(compoundParameter: Readonly<({
    templateElement: HTMLTemplateElement;
} | {
    templateElementSelector: string;
    contextElement?: ParentNode | Readonly<{
        selector: string;
    }>;
}) & {
    expectedChildElementSubtype: new () => DOM_ElementSubtype;
    mustReplaceTemplateElementOnceDoneWith?: Node;
    mustRemoveTemplateElementOnceDone?: true;
}>): DOM_ElementSubtype;
export default function getExpectedToBeSingleChildOfTemplateElement(compoundParameter: Readonly<({
    templateElement: HTMLTemplateElement;
} | {
    templateElementSelector: string;
    contextElement?: ParentNode | Readonly<{
        selector: string;
    }>;
}) & {
    mustReplaceTemplateElementOnceDoneWith?: Node;
    mustRemoveTemplateElementOnceDone?: true;
}>): Element;