def mask(array, predicates, new_value, ty):
    """
    Returns a new array, with each element in the original array satisfying the
    passed-in predicate set to `new_value`

    Args:
        array (WeldObject / Numpy.ndarray): Input array
        predicates (WeldObject / Numpy.ndarray<bool>): Predicate set
        new_value (WeldObject / Numpy.ndarray / str): mask value
        ty (WeldType): Type of each element in the input array

    Returns:
        A WeldObject representing this computation
    """
    weld_obj = WeldObject(encoder_, decoder_)

    array_var = weld_obj.update(array)
    if isinstance(array, WeldObject):
        array_var = array.obj_id
        weld_obj.dependencies[array_var] = array

    predicates_var = weld_obj.update(predicates)
    if isinstance(predicates, WeldObject):
        predicates_var = predicates.obj_id
        weld_obj.dependencies[predicates_var] = predicates

    if str(ty).startswith("vec"):
        new_value_var = weld_obj.update(new_value)
        if isinstance(new_value, WeldObject):
            new_value_var = new_value.obj_id
            weld_obj.dependencies[new_value_var] = new_value
    else:
        new_value_var = "%s(%s)" % (ty, str(new_value))

    weld_template = """
       map(
         zip(%(array)s, %(predicates)s),
         |p: {%(ty)s, bool}| if (p.$1, %(new_value)s, p.$0)
       )
    """
    weld_obj.weld_code = weld_template % {
        "array": array_var,
        "predicates": predicates_var,
        "new_value": new_value_var,
        "ty": ty}

    return weld_obj