If key and/or value is a node, it is copied to the mapping directly.
Otherwise it is converted to a node and then stored in the mapping.
It is possible for the same key to be present more than once in a
mapping. When emitting, all key-value pairs will be emitted.
This is useful with the "!!pairs" tag, but will result in
invalid YAML with "!!map" and "!!omap" tags.
Add a key-value pair to a mapping.
This method can only be called on mapping nodes.
If key and/or value is a node, it is copied to the mapping directly. Otherwise it is converted to a node and then stored in the mapping.
It is possible for the same key to be present more than once in a mapping. When emitting, all key-value pairs will be emitted. This is useful with the "!!pairs" tag, but will result in invalid YAML with "!!map" and "!!omap" tags.