type mapping = {
    [key: string]: any;
};
/**
 * Add a `key` property to the object `obj` with the value `value`.
 * @param obj - The input object.
 * @param key - The path in the resulting object to set the value.
 * @param value - The value to set.
 * @returns A deep copy of the object with the new property added.
 */
export declare function addProp(obj: object, key: string, value: any): object;
/**
 * Merges the values of the `prop` property from each object within the `objArr` array.
 * @param objArr - An array of objects.
 * @param prop - The path to the array property to merge.
 * @returns A deep copy of the first object in `objArr`, with its `prop` array containing the concatenated values from all objects in the `objArr`.
 */
export declare function mergeObjArr(objArr: object[], prop: string): object;
/**
 * Transforms the `source` object  based on the provided `mapping` transformation.
 *
 * @param source - A source object to transform.
 * @param mapping - A mapping object defining the transformation rules. Each mapping object's key-value pair should use JSONPath syntax:
 *   - The key represents the target field path in the transformed object.
 *   - The value represents the source field path(s) in the source object.
 *     - The value can be a literal.
 *     - If a single source field is required, the value should be a JSONPath string pointing to that field.
 *     - If a default value is needed, the value can be any valid JSON value.
 *     - If multiple source fields are required for applying a function, provide an array where:
 *       - Each element before the last is a JSONPath string pointing to a source field.
 *       - The last element is a function that takes the resolved source values as arguments and computes the target field value.
 *
 * @returns An array of transformed objects, with fields derived from applying the `mapping` to the `source` object.
 */
export declare function mapObj(source: object, mapping: mapping): object[];
/**
 * Transforms the `source` object  based on the provided `mapping` transformation.
 *
 * @param source - A source object to transform.
 * @param mapping - A mapping object defining the transformation rules. Each mapping object's key-value pair should use JSONPath syntax:
 *   - The key represents the target field path in the transformed object.
 *   - The value represents the source field path(s) in the source object.
 *     - The value can be a literal.
 *     - If a single source field is required, the value should be a JSONPath string pointing to that field.
 *     - If a default value is needed, the value can be any valid JSON value.
 *     - If multiple source fields are required for applying a sync or async function, provide an array where:
 *       - Each element before the last is a JSONPath string pointing to a source field.
 *       - The last element is a function that takes the resolved source values as arguments and computes the target field value.
 *
 * @returns An array of transformed objects, with fields derived from applying the `mapping` to the `source` object.
 */
export declare function mapObjAsync(source: object, mapping: mapping): Promise<object[]>;
/**
 * Transforms each object in the `source` array based on the provided `mapping` transformation.
 *
 * @param source - An array of source objects to transform.
 * @param mapping - A mapping object defining the transformation rules. Each mapping object's key-value pair should use JSONPath syntax:
 *   - The key represents the target field path in the transformed object.
 *   - The value represents the source field path(s) in the source object.
 *     - The value can be a literal.
 *     - If a single source field is required, the value should be a JSONPath string pointing to that field.
 *     - If a default value is needed, the value can be any valid JSON value.
 *     - If multiple source fields are required for applying a function, provide an array where:
 *       - Each element before the last is a JSONPath string pointing to a source field.
 *       - The last element is a function that takes the resolved source values as arguments and computes the target field value.
 *
 * @returns An array of transformed objects, with fields derived from applying the `mapping` to each `source` object.
 */
export declare function mapObjArr(source: object[], mapping: mapping): object[];
/**
 * Transforms each object in the `source` array based on the provided `mapping` transformation.
 *
 * @param source - An array of source objects to transform.
 * @param mapping - A mapping object defining the transformation rules. Each mapping object's key-value pair should use JSONPath syntax:
 *   - The key represents the target field path in the transformed object.
 *   - The value represents the source field path(s) in the source object.
 *     - The value can be a literal.
 *     - If a single source field is required, the value should be a JSONPath string pointing to that field.
 *     - If a default value is needed, the value can be any valid JSON value.
 *     - If multiple source fields are required for applying a sync or async function, provide an array where:
 *       - Each element before the last is a JSONPath string pointing to a source field.
 *       - The last element is a function that takes the resolved source values as arguments and computes the target field value.
 *
 * @returns An array of transformed objects, with fields derived from applying the `mapping` to each `source` object.
 */
export declare function mapObjArrAsync(source: object[], mapping: mapping): Promise<object[]>;
export {};