Macro yaml_peg::yaml_map

macro_rules! yaml_map {
    () => { ... };
    ($k1 : expr => $v1 : expr $(, $k2 : expr => $v2 : expr) * $(,) ?) => { ... };
}

Create YamlBase::Map items literally.

use yaml_peg::{node, yaml_map};
yaml_map!{
    node!("a") => node!("b"),
    node!("c") => node!("d"),
};