Impl TryGetableMany for diffrent types of generices (A, B, C)

[MuhannadAlrusayni]

Hi, I find that I cannot use the type (i32, Uuid, i32) as PrimaryKeyTrait::ValueType.

I think this is because TryGetableMany is only implemented for tuples with the same type (e.g. (i32, i32, i32)).

Solving this should be easy:

// change this:
impl<T> TryGetableMany for (T, T)
where
    T: TryGetable,
{
    fn try_get_many(res: &QueryResult, pre: &str, cols: &[String]) -> Result<Self, TryGetError> {
        try_get_many_with_slice_len_of(2, cols)?;
        Ok((
            T::try_get(res, pre, &cols[0])?,
            T::try_get(res, pre, &cols[1])?,
        ))
    }
}

// to this:
impl<T, U> TryGetableMany for (T, U)
where
    T: TryGetable,
    U: TryGetable,
{
    fn try_get_many(res: &QueryResult, pre: &str, cols: &[String]) -> Result<Self, TryGetError> {
        try_get_many_with_slice_len_of(2, cols)?;
        Ok((
            T::try_get(res, pre, &cols[0])?,
            U::try_get(res, pre, &cols[1])?,
        ))
    }
}