export declare function substring(str: any, start: any, end: any): any;
export declare function replaceSubstring(str: any, start: any, end: any, replacer: any): {
    value: string;
    caret: number;
};
export declare function isWhiteSpace(c: any): boolean;
export declare function getInputNodeForTrigger(node: Element | Text | null): HTMLInputElement | HTMLTextAreaElement | null;
export declare function getMenuListItems(suggestions: any, notFoundContent: any): any;