Macro create_structure_chain

Source
macro_rules! create_structure_chain {
    ($head:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty, $ext2:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty, $ext2:ty, $ext3:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty, $ext2:ty, $ext3:ty, $ext4:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty, $ext2:ty, $ext3:ty, $ext4:ty, $ext5:ty $(,)?) => { ... };
    ($head:ty, $ext1:ty, $ext2:ty, $ext3:ty, $ext4:ty, $ext5:ty, $ext6:ty $(,)?) => { ... };
}