/**
 * Format the `href` value for a link, when a user has finished typing.
 *
 * This function:
 *  - trims leading/trailing whitespace
 *  - ensures the value has a protocol (http://) if it doesn't already, unless
 *    it's a relative URL (starting with "/") or anchor (starting with "#")
 *  - URL-encodes the result
 *
 * @param value The value to format as an href (user-entered input value)
 * @returns The formatted value
 */
export declare function formatHref(value: string): string;