import type { EndpointConfig, EndpointOptions } from '../factories';
export declare const isDefined: <T>(value: T | null | undefined) => value is Exclude<T, null | undefined>;
export declare const isString: (value: unknown) => value is string;
export declare const createRequestParams: <Input extends Record<string | number, unknown> & ({} | {
    formData: Record<string, string | Blob>;
    requestBody?: undefined;
} | {
    requestBody: BodyInit;
    formData?: undefined;
})>(config: EndpointConfig, input: Input | null, options?: EndpointOptions) => [RequestInfo, RequestInit];