From: Thomas Walker Lynch <xtujpz@reasoningtechnology.com>
Date: Fri, 8 Nov 2024 16:02:26 +0000 (+0000)
Subject: .gitignore was missing in scratchpad, now added
X-Git-Url: https://git.reasoningtechnology.com/style/static/gitweb.css?a=commitdiff_plain;h=22af20169edff28bbb1dd12e1d5917ed2bef9adc;p=Ariadne

.gitignore was missing in scratchpad, now added
---

diff --git a/developer/javac/#Ariadne_GraphDirectedAcyclic.java# b/developer/javac/#Ariadne_GraphDirectedAcyclic.java#
new file mode 100644
index 0000000..26d01b2
--- /dev/null
+++ b/developer/javac/#Ariadne_GraphDirectedAcyclic.java#
@@ -0,0 +1,214 @@
+xopackage com.ReasoningTechnology.Ariadne;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.List;
+import java.util.ArrayList;
+
+public class Ariadne_GraphDirectedAcyclic extends Ariadne_Graph {
+
+  /*--------------------------------------------------------------------------------
+    Constructors
+  */
+
+  public Ariadne_GraphDirectedAcyclic(Map<Ariadne_Label, Ariadne_Node> node_map, Ariadne_ProductionList recognizer_f_list, Ariadne_LabelList root_node_list, int max_depth, boolean verbose) {
+    super(node_map, recognizer_f_list);
+    Ariadne_TokenSet cycle_detection_result = graph_mark_cycles(root_node_list, max_depth, verbose);
+  }
+
+  public Ariadne_GraphDirectedAcyclic(Map<Ariadne_Label, Ariadne_Node> node_map, Ariadne_ProductionList recognizer_f_list, Ariadne_LabelList root_node_list) {
+    super(node_map, recognizer_f_list);
+    Ariadne_TokenSet cycle_detection_result = graph_mark_cycles(root_node_list);
+  }
+
+  /*--------------------------------------------------------------------------------
+    Instance Data Extension
+  */
+
+  private static boolean debug = true;
+
+  /*--------------------------------------------------------------------------------
+    Interface
+  */
+
+  private List<Integer> path_find_cycle(Ariadne_LabelList path) {
+    if (path.size() <= 1) return null;
+
+    int rightmost_index = path.size() - 1;
+    Ariadne_Label rightmost_node_label = path.get(rightmost_index);
+
+    int cycle_leftmost_index = path.indexOf(rightmost_node_label);
+    Boolean has_cycle = cycle_leftmost_index < rightmost_index;
+    if (!has_cycle) return null;
+
+    List<Integer> result = new ArrayList<>();
+    result.add(cycle_leftmost_index);
+    result.add(rightmost_index);
+    return result;
+  }
+
+  private boolean graph_descend_cycle_case(Ariadne_LabelList left_path, List<Ariadne_LabelList> path_stack, boolean verbose) {
+
+    List<Integer> cycle_index_interval = path_find_cycle(left_path);
+    if (cycle_index_interval == null) {
+      return false;
+    }
+
+    int cycle_i0 = cycle_index_interval.get(0);
+    int cycle_n = cycle_index_interval.get(1);
+
+    if (verbose) Ariadne_Util.print_list(
+      "Found cycle:", 
+      left_path.subList(cycle_i0, cycle_n + 1)
+    );
+
+    Ariadne_LabelList undefined_node_list = new Ariadne_LabelList();
+    for (int i = cycle_i0; i <= cycle_n; i++) {
+      Ariadne_Label node_label = left_path.get(i);
+      Ariadne_Node node = super.lookup(node_label);
+      if (node != null) {
+        node.mark(new Ariadne_Token("cycle_member"));
+      } else {
+        undefined_node_list.add(node_label);
+      }
+    }
+
+    if (verbose) Ariadne_Util.print_list(
+      "Each undefined node could not be marked as a cycle member:", 
+      undefined_node_list
+    );
+
+    path_stack.subList(cycle_i0 + 1, cycle_n + 1).clear();
+
+    return true;
+  }
+
+  private static Ariadne_TokenSet graph_descend_set = new Ariadne_TokenSet() {{
+    add(new Ariadne_Token("empty_path_stack"));
+    add(new Ariadne_Token("cycle_found"));
+    add(new Ariadne_Token("undefined_node"));
+    add(new Ariadne_Token("leaf"));
+    add(new Ariadne_Token("max_depth_reached"));
+  }};
+
+  private Ariadne_TokenSet graph_descend(List<Ariadne_LabelList> path_stack, int max_depth, boolean verbose) {
+    Ariadne_TokenSet ret_value = new Ariadne_TokenSet();
+
+    if (path_stack.isEmpty()) {
+      ret_value.add(new Ariadne_Token("empty_path_stack"));
+      return ret_value;
+    }
+
+    Ariadne_LabelList left_path = new Ariadne_LabelList();
+    for (Ariadne_LabelList neighbor_list : path_stack) {
+      left_path.add(neighbor_list.get(0));
+    }
+
+    do {
+
+      if (graph_descend_cycle_case(left_path, path_stack, verbose)) {
+        ret_value.add(new Ariadne_Token("cycle_found"));
+        return ret_value;
+      }
+
+      Ariadne_Label it_node_label = path_stack.get(path_stack.size() - 1).get(0);
+      Ariadne_Node it_node = super.lookup(it_node_label);
+      if (it_node == null) {
+        ret_value.add(new Ariadne_Token("undefined_node"));
+        return ret_value;
+      }
+        
+      Ariadne_LabelList neighbor_list = it_node.neighbor_LabelList();
+      if (neighbor_list.isEmpty()) {
+        ret_value.add(new Ariadne_Token("leaf"));
+        return ret_value;
+      }
+
+      path_stack.add(new Ariadne_LabelList(neighbor_list));
+      Ariadne_Label it_next_label = neighbor_list.get(0);
+      left_path.add(it_next_label);
+
+      if (max_depth > 0) {
+        max_depth--;
+        if (max_depth == 0) {
+          if (verbose) {
+            Ariadne_Util.print_list("GraphDirectedAcyclic.GraphDescend:: max_depth reached, ending descent:", path_stack);
+          }
+          ret_value.add(new Ariadne_Token("max_depth_reached"));
+          return ret_value;
+        }
+      }
+
+    } while (true);
+  }
+
+  public static Ariadne_TokenSet graph_mark_cycles_set = new Ariadne_TokenSet() {{
+    add(new Ariadne_Token("empty_root_label_list"));
+    add(new Ariadne_Token("cycle_exists"));
+    add(new Ariadne_Token("undefined_node_exists"));
+    add(new Ariadne_Token("bad_descent_termination"));
+    add(new Ariadne_Token("max_depth_reached"));
+  }};
+
+  public Ariadne_TokenSet graph_mark_cycles(Ariadne_LabelList root_node_LabelList, int max_depth, boolean verbose) {
+    Ariadne_TokenSet ret_value = new Ariadne_TokenSet();
+    boolean exists_malformed = false;
+    Ariadne_TokenSet result;
+
+    if (root_node_LabelList.isEmpty()) {
+      ret_value.add(new Ariadne_Token("empty_root_label_list"));
+      return ret_value;
+    }
+
+    List<Ariadne_LabelList> path_stack = new ArrayList<>();
+    path_stack.add(new Ariadne_LabelList(root_node_LabelList));
+
+    do {
+      result = graph_descend(path_stack, max_depth, verbose);
+      if (result.contains(new Ariadne_Token("cycle_found"))) ret_value.add(new Ariadne_Token("cycle_exists"));
+      if (result.contains(new Ariadne_Token("undefined_node"))) ret_value.add(new Ariadne_Token("undefined_node_exists"));
+      if (result.contains(new Ariadne_Token("max_depth_reached"))) ret_value.add(new Ariadne_Token("max_depth_reached"));
+      if (!result.contains(new Ariadne_Token("leaf")) && !result.contains(new Ariadne_Token("cycle_found"))) ret_value.add(new Ariadne_Token("bad_descent_termination"));
+
+      Ariadne_LabelList top_list = path_stack.get(path_stack.size() - 1);
+      top_list.remove(0);
+      if (top_list.isEmpty()) path_stack.remove(path_stack.size() - 1);
+
+    } while (!path_stack.isEmpty());
+
+    if (verbose) {
+      if (ret_value.contains("bad_descent_termination")) {
+        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: terminated with unexpected condition.");
+      }
+      if (ret_value.contains("cycle_exists")) {
+        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: One or more cycles detected.");
+      }
+      if (ret_value.contains("undefined_node_exists")) {
+        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: Undefined nodes exist.");
+      }
+    }
+
+    return ret_value;
+  }
+
+  public Ariadne_TokenSet graph_mark_cycles(Ariadne_LabelList root_node_LabelList) {
+    return graph_mark_cycles(root_node_LabelList, this.debug ? 40 : -1, this.debug);
+  }
+
+  @Override
+  public Ariadne_Node lookup(Ariadne_Label node_label, boolean verbose) {
+    Ariadne_Node node = super.lookup(node_label, verbose);
+    if (node != null && node.has_mark(new Ariadne_Token("cycle_member"))) {
+      if (verbose) {
+        System.out.println("GraphDirectedAcyclic.lookup:: Node is part of a cycle, not returned: " + node_label);
+      }
+      return null;
+    }
+    return node;
+  }
+
+  public Ariadne_Node lookup(Ariadne_Label node_label) {
+    return lookup(node_label, this.debug);
+  }
+
+}
diff --git a/developer/scratchpad/.gitignore b/developer/scratchpad/.gitignore
new file mode 100644
index 0000000..120f485
--- /dev/null
+++ b/developer/scratchpad/.gitignore
@@ -0,0 +1,2 @@
+*
+!/.gitignore
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_File.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_File.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_GraphDirectedAcyclic$1.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_GraphDirectedAcyclic$1.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Label.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Label.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Node.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Node.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Production.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Production.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Token.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Token.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Util.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Ariadne_Util.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/File.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/File.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/File.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/File.java
deleted file mode 100644
index 825b499..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/File.java
+++ /dev/null
@@ -1,76 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-
-import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
-import java.nio.file.Paths;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
-public class Ariadne_File {
-  static boolean debug = false;
-
-  public static Map<String, String> unpack_file_path(String file_fp) {
-    if (debug) System.out.println("unpack_file_path::file_fp: " + file_fp);
-
-    // Use java.io.File explicitly to avoid conflict with the custom Ariadne_File class
-    java.io.File file = new java.io.File(file_fp);
-    String parent_dp = (file.getParent() != null) ? file.getParent() : "";
-
-    if (!parent_dp.isEmpty() && !parent_dp.endsWith(java.io.File.separator)) {
-      parent_dp += java.io.File.separator;
-    }
-
-    String file_fn = file.getName();
-    String file_fn_base = file_fn;
-    String file_fn_ext = "";
-
-    int last_index = file_fn.lastIndexOf('.');
-    if (last_index > 0) {
-      file_fn_base = file_fn.substring(0, last_index);
-      if (last_index + 1 < file_fn.length()) {
-        file_fn_ext = file_fn.substring(last_index + 1);
-      }
-    }
-
-    Map<String, String> ret_val = new HashMap<>();
-    ret_val.put("dp", parent_dp);
-    ret_val.put("fn", file_fn);
-    ret_val.put("fn_base", file_fn_base);
-    ret_val.put("fn_ext", file_fn_ext);
-
-    if (debug) System.out.println("unpack_file_path::ret_val: " + ret_val);
-
-    return ret_val;
-  }
-
-  public static boolean file_exists_q(String fp_string) {
-    Path fp_object = Paths.get(fp_string);
-    return Files.exists(fp_object);
-  }
-
-  /*
-    Given a target_fp and a list of dependency_fp.
-
-    Returns false if the target is newer than all dependencies or if a file is missing;
-    otherwise, returns true.
-  */
-  public static boolean newer_than_all(String target_fp_string, List<String> dependency_fp_list) throws IOException {
-    Path target_fp_object = Paths.get(target_fp_string);
-    if (!Files.exists(target_fp_object)) return false;
-
-    long target_last_modified_time = Files.getLastModifiedTime(target_fp_object).toMillis();
-
-    return dependency_fp_list.stream().allMatch(dependency_fp -> {
-      try {
-        Path dependency_fp_object = Paths.get(dependency_fp);
-        if (!Files.exists(dependency_fp_object)) return false;
-        long dependency_last_modified_time = Files.getLastModifiedTime(dependency_fp_object).toMillis();
-        return target_last_modified_time > dependency_last_modified_time;
-      } catch (IOException e) {
-        return false;
-      }
-    });
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Graph.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Graph.class
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index 36d6001..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Graph.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Graph.java
deleted file mode 100644
index d50c429..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Graph.java
+++ /dev/null
@@ -1,63 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-
-import java.util.HashMap;
-import java.util.Map;
-
-public class Graph{
-
-  /*--------------------------------------------------------------------------------
-    constructors
-  */
-
-  public Graph(Map<Label ,Node> node_map ,ProductionList recognizer_f_list){
-    if(node_map == null && recognizer_f_list == null){
-      System.err.println("AriadneGraph: At least one of 'node_map' (Map) or 'recognizer_f_list' (List) must be provided.");
-      System.exit(1);
-    }
-
-    // Initialize each of node_map and recognizer_f_list to empty collections if null
-    this.node_map = (node_map != null) ? node_map : new HashMap<Label ,Node>();
-    this.recognizer_f_list = (recognizer_f_list != null) ? recognizer_f_list : new ProductionList();
-  }
-
-  /*--------------------------------------------------------------------------------
-   instance data 
-  */
-
-  private static boolean debug = true;
-  private Map<Label ,Node> node_map;
-  private ProductionList recognizer_f_list;
-
-  /*--------------------------------------------------------------------------------
-   interface
-  */
-
-  // Lookup method to find a node by its label
-  public Node lookup(Label node_label ,boolean verbose){
-    if( node_label == null || node_label.isEmpty() ){
-      if(verbose){
-        System.out.println("lookup:: given node_label is null or empty.");
-      }
-      return null;
-    }
-
-    // Try to retrieve the node from the map
-    Node node = this.node_map.get(node_label);
-
-    if(verbose){
-      if(node != null){
-        System.out.println("lookup:: found node: " + node);
-      } else {
-        System.out.println("lookup:: node not found for label: " + node_label);
-      }
-    }
-
-    return node;
-  }
-
-  // Overloaded lookup method with default verbosity (true)
-  public Node lookup(Label node_label){
-    return lookup(node_label ,true);
-  }
-
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic$1.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic$1.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic$2.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic$2.class
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic.class
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index e987c4b..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic.java
deleted file mode 100644
index f01e8de..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/GraphDirectedAcyclic.java
+++ /dev/null
@@ -1,282 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-
-import java.util.HashMap;
-import java.util.Map;
-import java.util.List;
-import java.util.ArrayList;
-
-public class GraphDirectedAcyclic extends Graph{
-
-  /*--------------------------------------------------------------------------------
-    constructors
-  */
-
-  public GraphDirectedAcyclic(Map<Label ,Node> node_map ,ProductionList recognizer_f_list ,LabelList root_node_list ,int max_depth ,boolean verbose){
-    super( node_map ,recognizer_f_list );
-    TokenSet cycle_detection_result = graph_mark_cycles(root_node_list ,max_depth ,verbose);
-  }
-
-  public GraphDirectedAcyclic(Map<Label ,Node> node_map ,ProductionList recognizer_f_list ,LabelList root_node_list){
-    super( node_map ,recognizer_f_list );
-    TokenSet cycle_detection_result = graph_mark_cycles(root_node_list);
-  }
-
-
-  /*--------------------------------------------------------------------------------
-   instance data extension
-  */
-
-  private static boolean debug = true;
-
-
-  /*--------------------------------------------------------------------------------
-    Interface
-  */
-
-  /*
-    Given a path to a node in the graph, `left_path`.
-
-    Checks if the rightmost node (referenced by label) recurs earlier in the path.
-    Presumably the rightmost node has been recently appended to the path.
-
-    If there is no cycle, returns null, otherwise returns the interval [i ,n],
-    of indexes into the path where the cycle is found. `n` will always be
-    the index of the rightmost node in the path list.
-  */
-  private List<Integer>  path_find_cycle(LabelList path ){
-    if( path.size() <= 1 ) return null; 
-
-    int rightmost_index = path.size() - 1;
-    Label rightmost_node_label = path.get( rightmost_index );
-
-    // if there is no cycle, searching for rightmost_node_label will find itself:
-    int cycle_leftmost_index = path.indexOf(rightmost_node_label);
-    Boolean has_cycle = cycle_leftmost_index < rightmost_index;
-    if( ! has_cycle ) return null;
-
-    List<Integer> result = new ArrayList<>();
-    result.add(cycle_leftmost_index);
-    result.add(rightmost_index);
-    return result;
-  }
-
-  /*
-    Given a path_stack, which is our graph iterator.  Also given `left_path`
-    which is derived from path_stack, and represents the left most neighbor
-    of each of the neighbor lists in the path_stack.
-
-    Calls `path_find_cycle` to see if the most recently added to the path node,
-    i.e. the rightmost node, forms a cycle with other node(s) in the path.  Upon
-    finding a cycle, unwinds the path_stack (decrements the iterator), to the top
-    of the cycle.
-
-    If a cycle is found, returns false, otherwise returns true.
-  */
-  private boolean graph_descend_cycle_case( LabelList left_path ,List<LabelList> path_stack ,boolean verbose ){
-
-    List<Integer> cycle_index_interval = path_find_cycle(left_path);
-    if( cycle_index_interval == null ){
-      return false; // No cycle found
-    }
-
-    int cycle_i0 = cycle_index_interval.get(0); // Cycle leftmost, inclusive
-    int cycle_n = cycle_index_interval.get(1);  // Cycle rightmost, inclusive
-
-    if(verbose) Util.print_list(
-      "Found cycle:" 
-      ,left_path.subList( cycle_i0 ,cycle_n + 1)
-    );
-
-    // Mark cycle members
-    LabelList undefined_node_list = new LabelList();
-    for( int i = cycle_i0; i <= cycle_n; i++ ){
-      Label node_label = left_path.get(i);
-      Node node = super.lookup( node_label );
-      if (node != null){
-        node.mark(new Token("cycle_member"));
-      }else{
-        undefined_node_list.add( node_label );
-      }
-    }
-
-    if(verbose) Util.print_list(
-      "Each undefined node could not be marked as a cycle member:" 
-      ,undefined_node_list
-    );
-
-    // Reset the graph iterator to the top of the cycle
-    path_stack.subList( cycle_i0 + 1 ,cycle_n + 1 ).clear();
-
-    return true; // cycle found
-  }
-  
-  /*
-    Given a path_stack initialized to the root nodes for the graph traversal.
-
-    Perform depth first descent from each node in succession while searching for
-    cycles by calling graph_descent_cycle_case. Algorithm follows the leftmost
-    nodes in the path_stack list of child lists.
-
-    Returns the descent termination condition.
-  */
-  private static TokenSet graph_descend_set = new TokenSet() {{
-    add(new Token("empty_path_stack"));
-    add(new Token("cycle_found"));
-    add(new Token("undefined_node"));
-    add(new Token("leaf"));
-    add(new Token("max_depth_reached"));
-  }};
-  private TokenSet graph_descend( List<LabelList> path_stack ,int max_depth ,boolean verbose ){
-    TokenSet ret_value = new TokenSet();
-
-    if( path_stack.isEmpty() ){
-      ret_value.add( new Token("empty_path_stack") );
-      return ret_value;
-    }
-
-    // a leftmost path through the neighbor lists of the leftmost nodes
-    LabelList left_path = new LabelList();
-    for( LabelList neighbor_list : path_stack ){
-      left_path.add( neighbor_list.get(0) );
-    }
-
-    // do descend
-    do{
-
-      // cycle case
-      if( graph_descend_cycle_case( left_path ,path_stack ,verbose ) ){
-        ret_value.add( new Token("cycle_found") );
-        return ret_value;
-      }
-
-      // Non-cycle case, descend further into the tree.
-      // Increment the graph iterator (path_stack) to go down a level.
-      Label it_node_label = path_stack.get( path_stack.size() - 1 ).get(0);
-      Node it_node = super.lookup( it_node_label );
-      if( it_node == null ){
-        ret_value.add( new Token("undefined_node") );
-        return ret_value;
-      }
-        
-      LabelList neighbor_list = it_node.neighbor_LabelList();
-      if( neighbor_list.isEmpty() ){
-        ret_value.add( new Token("leaf") );
-        return ret_value;
-      }
-
-      // The iterator will destroy the neighbor_list as we traverse the graph,
-      // so we give it a copy.
-      path_stack.add( new LabelList(neighbor_list) );
-      Label it_next_label = neighbor_list.get(0);
-      left_path.add( it_next_label ); // also extend the left_path
-
-      // bound the size of problem we are willing to work on
-      // set max_depth <= 0 to have this test ignored
-      if( max_depth > 0 ){
-        max_depth--;  // Typo fixed
-        if( max_depth == 0 ){
-          if(verbose){
-            Util.print_list("GraphDirectedAcyclic.GraphDescend:: max_depth reached, preternaturally ending the descent:" ,path_stack);
-          }
-          ret_value.add( new Token("max_depth_reached") );
-          return ret_value;
-        }
-      }
-
-    }while(true); // while descend
-  }
-
-   
-  /*
-    Given root_node_label_list and a maximum depth for traversal.
-
-    Cycles are handled gracefully, rather the constraint `max_depth` is present
-    because the user is allowed to provide production *functions* for generating
-    nodes. Who knows what crazy graphs a user could come up with, see the
-    document on the algorithm for more info.
-  
-    Does a left first depth first traversal of the graph while marking
-    cycles. This routine pushes the graph traversal iterator to the right one
-    node after a left descent traversal, then it calls `graph_descend` descend
-    from said node.
-
-    Returns one or more symbols that characterize the termination condition.
-  */
-
-  public static TokenSet graph_mark_cycles_set = new TokenSet() {{
-    add(new Token("empty_root_label_list"));
-    add(new Token("cycle_exists"));
-    add(new Token("undefined_node_exists"));
-    add(new Token("bad_descent_termination"));
-    add(new Token("max_depth_reached"));
-  }};
-  public TokenSet graph_mark_cycles( LabelList root_node_LabelList ,int max_depth ,boolean verbose ){
-    TokenSet ret_value = new TokenSet();
-    boolean exists_malformed = false;
-    TokenSet result; // used variously
-
-    if( root_node_LabelList.isEmpty() ){
-      ret_value.add(new Token("empty_root_label_list"));
-      return ret_value;
-    }
-
-    // `path_stack` is our graph iterator. It is initialized with the
-    // `root_node_LabelList`.
-    List<LabelList> path_stack = new ArrayList<>();
-    path_stack.add( new LabelList(root_node_LabelList) );
-
-    // each call to graph_descend does a leftmost descent to a leaf
-    do{
-      result = graph_descend( path_stack ,max_depth ,verbose );
-      if( result.contains(new Token("cycle_found")) ) ret_value.add(new Token("cycle_exists"));
-      if( result.contains(new Token("undefined_node")) ) ret_value.add(new Token("undefined_node_exists"));
-      if( result.contains(new Token("max_depth_reached")) ) ret_value.add(new Token("max_depth_reached"));
-      if( !result.contains(new Token("leaf")) && !result.contains(new Token("cycle_found")) ) ret_value.add(new Token("bad_descent_termination"));
-
-      // Push the iterator to the right by one node
-      LabelList top_list = path_stack.get( path_stack.size() - 1 );
-      top_list.remove(0);
-      if( top_list.isEmpty() ) path_stack.remove( path_stack.size() - 1 );
-
-    }while( !path_stack.isEmpty() );
-
-    if(verbose){
-      if( ret_value.contains("bad_descent_termination") ){
-        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: graph_descend terminated with other than leaf or cycle found condition.");
-      }
-      if( ret_value.contains("cycle_exists") ){
-        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: There are one or more cycles in the graph.");
-      }
-      if( ret_value.contains("undefined_node_exists") ){
-        System.out.println("GraphDirectedAcyclic.graph_mark_cycles:: There are one or more node label references that do not correspond to a defined node in this graph.");
-      }
-    }
-
-    return ret_value;
-  }
-   public TokenSet graph_mark_cycles(LabelList root_node_LabelList){
-    return graph_mark_cycles(root_node_LabelList ,this.debug?40:-1 ,this.debug);
-  }
-  
-
-  /*--------------------------------------------------------------------------------
-    Graph traversal
-  */
-
-  @Override
-  public Node lookup(Label node_label, boolean verbose){
-    Node node = super.lookup(node_label, verbose);
-    if(node != null && node.has_mark(new Token("cycle_member"))){
-      if(verbose){
-        System.out.println("GraphDirectedAcyclic.lookup:: Node is part of a cycle so it will not be returned: " + node_label);
-      }
-      return null;  // Exclude nodes in cycles
-    }
-    return node;
-  }
-
-  public Node lookup(Label node_label){
-    return lookup(node_label ,this.debug);
-  }
-
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.class
deleted file mode 100644
index 0bd129e..0000000
Binary files a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.class and /dev/null differ
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.java
deleted file mode 100644
index 3d13f45..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Label.java
+++ /dev/null
@@ -1,42 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-
-/*
-  A value for the node.label property.
-
-  This is a wrapper for a String. We can't instead use an alias by extending
-  String, because String is a JavaScript 'final' type.
-
-*/
-public class Label {
-  private final String value;
-
-  public Label(String value){
-    this.value = value;
-  }
-
-  public boolean isEmpty() {
-    return value.isEmpty();
-  }
-
-  public String get(){
-    return value;
-  }
-
-  @Override
-  public String toString(){
-    return value;
-  }
-
-  @Override
-  public boolean equals(Object o){
-    if(this == o) return true;
-    if( o == null || getClass() != o.getClass() ) return false;
-    Label label = (Label)o;
-    return value.equals( label.value );
-  }
-
-  @Override
-  public int hashCode(){
-    return value.hashCode();
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/LabelList.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/LabelList.class
deleted file mode 100644
index 40f1a97..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/LabelList.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/LabelList.java
deleted file mode 100644
index 85acde8..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/LabelList.java
+++ /dev/null
@@ -1,18 +0,0 @@
-// LabelList.java
-package com.ReasoningTechnology.Ariadne;
-import java.util.List; 
-import java.util.ArrayList;
-
-public class LabelList extends ArrayList<Label> {
-  // Constructor
-  public LabelList(){
-    super();
-  }
-  public LabelList(List<Label> labels){
-    super();  // Initialize the parent class
-    if (labels != null) {
-      this.addAll(labels);  // Copy all elements from the provided list
-    }
-  }
-
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Node.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Node.class
deleted file mode 100644
index a00c7a5..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Node.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Node.java
deleted file mode 100644
index db0aa8d..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Node.java
+++ /dev/null
@@ -1,34 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-import java.util.HashMap;
-import java.util.ArrayList;
-import java.util.List;
-
-public class Node extends HashMap<String, Object>{
-
-  private static String mark_property_name = "mark";
-  private static String neighbor_property_name = "neighbor";
-
-  public Node(){
-    super();
-    // Initialize the neighbor list in the constructor
-    this.put(neighbor_property_name, new LabelList());
-  }
-
-  public void mark(Token token){
-    if( this.get(mark_property_name) == null ){
-      this.put(mark_property_name, new TokenSet());
-    }
-    ((TokenSet)this.get(mark_property_name)).add(token);
-  }
-
-  public boolean has_mark(Token token){
-    TokenSet mark = (TokenSet)this.get(mark_property_name);
-    return mark != null && mark.contains(token);
-  }
-
-  // Return the neighbor list (always exists after initialization)
-  public LabelList neighbor_LabelList(){
-    return (LabelList)this.get(neighbor_property_name);
-  }
-
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/NodeList.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/NodeList.class
deleted file mode 100644
index 4897461..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/NodeList.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/NodeList.java
deleted file mode 100644
index 189cf83..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/NodeList.java
+++ /dev/null
@@ -1,10 +0,0 @@
-// NodeList.java
-package com.ReasoningTechnology.Ariadne;
-import java.util.ArrayList;
-
-public class NodeList extends ArrayList<Node> {
-  // Constructor
-  public NodeList(){
-    super();
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Production.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Production.class
deleted file mode 100644
index 8fb153c..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Production.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Production.java
deleted file mode 100644
index 1639c56..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Production.java
+++ /dev/null
@@ -1,5 +0,0 @@
-// Production.java
-package com.ReasoningTechnology.Ariadne;
-import java.util.function.Function;
-
-public interface Production extends Function<Label, Node> {}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/ProductionList.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/ProductionList.class
deleted file mode 100644
index 73b5e2c..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/ProductionList.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/ProductionList.java
deleted file mode 100644
index 7973193..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/ProductionList.java
+++ /dev/null
@@ -1,10 +0,0 @@
-// ProductionList.java
-package com.ReasoningTechnology.Ariadne;
-import java.util.ArrayList;
-
-public class ProductionList extends ArrayList<Production> {
-  // Constructor
-  public ProductionList(){
-    super();
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Token.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Token.class
deleted file mode 100644
index 9c65237..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Token.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Token.java
deleted file mode 100644
index 37d7c2b..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Token.java
+++ /dev/null
@@ -1,35 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-
-/*
-An error token.
-
-*/
-public class Token {
-  private final String value;
-
-  public Token(String value){
-    this.value = value;
-  }
-
-  public String get(){
-    return value;
-  }
-
-  @Override
-  public String toString(){
-    return value;
-  }
-
-  @Override
-  public boolean equals(Object o){
-    if(this == o) return true;  // No padding, not nested
-    if( o == null || getClass() != o.getClass() ) return false;  // Padded, because it's nested
-    Token token = (Token)o;
-    return value.equals( token.value );
-  }
-
-  @Override
-  public int hashCode(){
-    return value.hashCode();
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/TokenSet.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/TokenSet.class
deleted file mode 100644
index ec7275e..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/TokenSet.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/TokenSet.java
deleted file mode 100644
index a05443f..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/TokenSet.java
+++ /dev/null
@@ -1,10 +0,0 @@
-// TokenSet.java
-package com.ReasoningTechnology.Ariadne;
-import java.util.HashSet;
-
-public class TokenSet extends HashSet<Token> {
-  // Constructor
-  public TokenSet(){
-    super();
-  }
-}
diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Util.class b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Util.class
deleted file mode 100644
index 4e01d3d..0000000
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diff --git a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Util.java b/developer/scratchpad/com/ReasoningTechnology/Ariadne/Util.java
deleted file mode 100644
index 571e7e3..0000000
--- a/developer/scratchpad/com/ReasoningTechnology/Ariadne/Util.java
+++ /dev/null
@@ -1,25 +0,0 @@
-package com.ReasoningTechnology.Ariadne;
-import java.util.List; 
-
-public class Util{
-  static boolean debug = false;
-
-  public static void print_list(String prefix ,List<?> item_list){
-    if( item_list == null || item_list.isEmpty() ){
-      return;
-    }
-    if( prefix != null && !prefix.isEmpty() ){
-      System.out.print(prefix);
-    }
-    int i = 0;
-    int n = item_list.size() - 1;
-    System.out.print( " '" + item_list.get(i) + "'" );
-    do{
-      i++;
-      if( i > n ) break;
-      System.out.print(", " +  "'" + item_list.get(i) + "'");
-    }while( true );
-    System.out.println(".");
-  }
-
-}
diff --git a/tester/scratchpad/.gitignore b/tester/scratchpad/.gitignore
new file mode 100644
index 0000000..120f485
--- /dev/null
+++ b/tester/scratchpad/.gitignore
@@ -0,0 +1,2 @@
+*
+!/.gitignore
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deleted file mode 100644
index c1af96b..0000000
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