Macro parse_container_node_variables

macro_rules! parse_container_node_variables {
    ($pair:ident, $context:ident) => { ... };
    ($pair:ident, $context:ident, named) => { ... };
    ($pair:ident, $context:ident, availability) => { ... };
    ($pair:ident, $context:ident, named, availability) => { ... };
}