Represents a YAML stream. This is the root node for any YAML parse tree. This node must have one or more child nodes. The only valid child node for a Psych::Nodes::Stream node is Psych::Nodes::Document.
UTF16BE = Psych::Parser::UTF16BE
UTF16LE = Psych::Parser::UTF16LE
UTF8 = Psych::Parser::UTF8
ANY = Psych::Parser::ANY
The encoding used for this stream