def add(lhs, rhs, ctx):
    """Element +
    (num, num) -> lhs + rhs
    (num, str) -> str(lhs) + rhs
    (str, num) -> lhs + str(rhs)
    (str, str) -> lhs + rhs
    """

    ts = vy_type(lhs, rhs)
    return {
        (NUMBER_TYPE, NUMBER_TYPE): lambda: lhs + rhs,
        (NUMBER_TYPE, str): lambda: str(lhs) + rhs,
        (str, NUMBER_TYPE): lambda: lhs + str(rhs),
        (str, str): lambda: lhs + rhs,
    }.get(ts, lambda: vectorise(add, lhs, rhs, ctx=ctx))()

def mold(
    content: Union[list, LazyList.LazyList],
    shape: Union[list, LazyList.LazyList],
) -> Union[list, LazyList.LazyList]:
    """Mold one list to the shape of the other. Uses the mold function
    that Jelly uses."""
    # github.com/DennisMitchell/jellylanguage/blob/…
    for index in range(len(shape)):
        if type(shape[index]) == list:
            mold(content, shape[index])
        else:
            item = content.pop(0)

def log_mold_multi(lhs, rhs, ctx):
    """Element •
    (num, num) -> log_lhs(rhs)
    (num, str) -> [char * lhs for char in rhs]
    (str, num) -> [char * rhs for char in lhs]
    (str, str) -> lhs.with_capitalisation_of(rhs)
    (lst, lst) -> lhs molded to the shape of rhs
    """

    ts = vy_type(lhs, rhs, True)

    return {
        (NUMBER_TYPE, NUMBER_TYPE): lambda: sympy.Rational(math.log(lhs, rhs)),
        (NUMBER_TYPE, str): lambda: "".join([char * lhs for char in rhs]),
        (str, NUMBER_TYPE): lambda: "".join([char * rhs for char in lhs]),