parser

type Node interface {
	// GetNext returns the next node of the current node.
	GetNext() Node

	// GetChildren returns the children nodes of the current node.
	GetChildren() []Node

	// GetValue returns the value of the current node, the value is
	// the command or the args of the line by parsing the modelfile.
	GetValue() string

	// GetAttributes returns the attributes of the current node, such as key-value pairs.
	// Attributes can be used to expand the information of the node.
	GetAttributes() map[string]string

	// GetStartLine returns the start line of the current node, it will help to
	// locate the start of the node.
	GetStartLine() int

	// GetEndLine returns the end line of the current node, it will help to
	// locate the end of the node.
	GetEndLine() int

	// AddChild adds a child node to the current node.
	AddChild(child Node)

	// AddNext adds a next node to the current node.
	AddNext(next Node)

	// AddAttribute adds an attribute to the current node.
	AddAttribute(key, value string)
}