[Fact] public void HierarchyOutput()
{
var node4 = new RankedNode();
var node5 = new RankedNode(node4);
var node6 = new ValueNode <int>(node5, 9);
var node7 = new ValueNode <int>(node5, 7);
var node1 = new RankedNode(node4);
var node2 = new ValueNode <int>(node1, 6);
var node3 = new ValueNode <int>(node1, 3);
var node8 = new RankedNode(node4);
var node9 = new ValueNode <int>(node8, 5);
var node10 = new ValueNode <int>(node8, 2);
var hier = new Hierarchy <int>(node4);
// T.FileWriter.SetDirAndFile("Tests", nameof(hier), ".txt");
// T.FileWriter.WriteLine(hier);
hier.MakeTopNode(node5);
// T.FileWriter.WriteLine(hier);
hier.MakeTopNode(node4);
// T.FileWriter.WriteLine(hier);
// T.FileWriter.Flush();
var strw = new StringWriter();
strw.Write <int>(hier);
Assert.True(strw.ToString() == "{{9, 7}, {6, 3}, {5, 2}}");
}
/// <summary>Attempts to read a data stream fed by a text reader as a hierarchy. Throws an exception if the data is not convertible to a hierarchy.</summary>
/// <param name="tr">Text reader such as FileReader.</param>
/// <typeparam name="τ">Type of Hierarchy elements.</typeparam>
public static Hierarchy <τ>?ReadHierarchy <τ>(this TextReader tr)
where τ : IEquatable <τ>, new()
{
var nFI = new NumberFormatInfo();
nFI.NumberDecimalSeparator = ".";
var types = new Type[] { typeof(string), typeof(IFormatProvider) };
var parseMethod = typeof(τ).GetMethod("Parse", types);
if (parseMethod == null)
{
throw new NullReferenceException("Parse method not found.");
}
var parse = (Func <string, IFormatProvider, τ>)Delegate.CreateDelegate(
typeof(Func <string, IFormatProvider, τ>), parseMethod);
var wholeStr = tr.ReadToEnd();
var sb = new StringBuilder(@"(\w+\.?\w*|", 300);
sb.Append(@"\{ ");
sb.Append(@" (?> ");
sb.Append(@" [^{}]+ ");
sb.Append(@" | ");
sb.Append(@" \{ (?<DEPTH>) ");
sb.Append(@" | ");
sb.Append(@" } (?<-DEPTH>) ");
sb.Append(@" )* ");
sb.Append(@" (?(DEPTH)(?!)) ");
sb.Append(@"} ");
sb.Append(@")"); // The end of an alternator from first line.
var matcher = new Regex(sb.ToString(), RegexOptions.IgnorePatternWhitespace,
new TimeSpan(0, 0, 1));
var firstMatch = matcher.Match(wholeStr);
if (firstMatch.Success) // Now check elements inside it.
{
var topNode = new RankedNode();
var hier = new Hierarchy <τ>(topNode);
Recursion(firstMatch.Value, topNode);
return(hier);
}
else
{
return(null);
}
void Recursion(string prevMatched, RankedNode nodeAbove)
{
var sb2 = new StringBuilder(prevMatched, 300);
sb2.Remove(prevMatched.Length - 1, 1).Remove(0, 1); // Strip it of outer braces.
prevMatched = sb2.ToString(); // Now it is without outer braces.
Match newMatch = matcher.Match(prevMatched); // Match either first value or braces
while (newMatch.Success) // If there was anything inside at all.
{
if (newMatch.Value[0] == '{') // If it was a non-value node.
{
Recursion(newMatch.Value, new RankedNode(nodeAbove));
}
else // If it was a value node.
{
new ValueNode <τ>(nodeAbove, parse(newMatch.Value, nFI));
}
newMatch = newMatch.NextMatch();
}
}
}
