Macro seq_impl

macro_rules! seq_impl {
    (
        $(#[$attr:meta])*
        $ty:ident <T $(: $tbound1:ident $(+ $tbound2:ident)*)* $(, $typaram:ident : $bound1:ident $(+ $bound2:ident)*)*>,
        $access:ident,
        $clear:expr,
        $with_capacity:expr,
        $reserve:expr,
        $insert:expr
    ) => { ... };
}