/// <summary>Generates a Unique ID for a parse tree node</summary>
/// <param name="tree">parse tree to generate the id for</param>
/// <returns>ID for the node</returns>
/// <remarks>
/// This is useful when generating various graph visualization file formats as
/// they normally need unique IDs for each node to maintain proper references
/// between the nodes.
/// </remarks>
public static string GetUniqueNodeId(this IParseTree tree)
{
tree.ValidateNotNull(nameof(tree));
var bldr = new StringBuilder(tree.GetHashCode( ).ToString(CultureInfo.InvariantCulture));
if (tree.Parent != null)
{
bldr.Append(tree.Parent.GetChildIndex(tree));
bldr.Append(tree.Parent.GetUniqueNodeId( ));
}
return(bldr.ToString( ));
}
/// <summary>Determines the index of a child item in the parent</summary>
/// <param name="tree">Parent tree to find the item in</param>
/// <param name="item">Item to determine the index of</param>
/// <returns>Zero based index in the parent or -1 if the item is not a child of <paramref name="tree"/></returns>
public static int GetChildIndex(this IParseTree tree, IParseTree item)
{
tree.ValidateNotNull(nameof(tree));
for (int i = 0; i < tree.ChildCount; ++i)
{
if (item == tree.GetChild(i))
{
return(i);
}
}
return(-1);
}
