needed for binding (added temporarily)

3 files changed, 100 insertions, 0 deletions

diff --git a/sources/scala/SeqTrace.scala b/sources/scala/SeqTrace.scala
new file mode 100644
index 0000000000..505d19ecff
--- /dev/null
+++ b/sources/scala/SeqTrace.scala
@@ -0,0 +1,55 @@
+// needed for variable binding in pattern matching
+
+package scala;
+
+        // special sequence list
+
+        // run of a left-transducer that tags its input with states
+
+        // needed for variable binding during matching
+
+        abstract class SeqTrace[ a ] extends List[ Tuple2[ Int, a ] ] {
+
+             /*abstract*/ def isEmpty:Boolean ;
+
+             /*abstract*/ def head:Tuple2[ Int, a ];
+
+             /*abstract*/ def headState:Int;
+
+	     /*abstract*/ def headElem:a;
+
+
+             /*abstract*/ def tail:SeqTrace[ a ];
+
+        /*
+             override def ::(zI:Int, za:a): SeqTrace[ a ] =
+                   new SeqTraceCons (zI, za, this ) ;
+*/
+             // why the f&&k do I need the .as cast ?
+
+             def add[ a ]( state:Int, value:a ):SeqTraceCons[ a ] =
+                   SeqTraceCons[a](state, value, this as SeqTrace[ a ] );
+
+      // this is copied verbatim from List... and SeqList
+	 def mkString2(start: java.lang.String,
+		     sep: java.lang.String,
+		     end: java.lang.String): java.lang.String =
+		       start +
+		      (if (isEmpty) end
+			 else if (tail.isEmpty) head.toString() + end
+			       else head.toString().concat(sep).concat(
+				             tail.mkString2("", sep, end)));
+/* BUG
+override def mkString(start: java.lang.String,
+		     sep: java.lang.String,
+		     end: java.lang.String): java.lang.String =
+		       start +
+		      (if (isEmpty) end
+			 else if (tail.isEmpty) head.toString() + end
+			       else head.toString().concat(sep).concat(
+				             tail.mkString("", sep, end)));
+*/
+
+        }
+
+
diff --git a/sources/scala/SeqTraceCons.scala b/sources/scala/SeqTraceCons.scala
new file mode 100644
index 0000000000..4b5724d8fe
--- /dev/null
+++ b/sources/scala/SeqTraceCons.scala
@@ -0,0 +1,22 @@
+package scala;
+
+  /** nonempty SeqTrace
+   */
+  final case class SeqTraceCons[ b ]( hdI:Int, hdb:b, tl: SeqTrace[ b ] )
+    extends SeqTrace[ b ]  {
+
+	  def isEmpty = false;
+
+	  def head = Tuple2( hdI, hdb );
+
+	  def headState = hdI;
+
+	  def headElem  = hdb;
+
+	  def tail = tl;
+
+	  override def toString(): String = mkString2("[ ", "; ", " ]");
+
+    }
+
+
diff --git a/sources/scala/SeqTraceNil.scala b/sources/scala/SeqTraceNil.scala
new file mode 100644
index 0000000000..56269ecd5b
--- /dev/null
+++ b/sources/scala/SeqTraceNil.scala
@@ -0,0 +1,23 @@
+// BE
+
+package scala ;
+
+    // SeqNil (empty SeqList)
+
+    final case class SeqTraceNil[ c ]() extends SeqTrace[ c ]  {
+
+	  def isEmpty = true;
+
+	  def head: Tuple2[ Int, c ] = error("head of empty Trace");
+
+	  def headState: Int = error("headState of empty Trace");
+
+	  def headElem: c = error("headElem of empty Trace");
+
+	  def tail: SeqTraceNil[c] = error("tail of empty Trace");
+
+	  override def toString(): String = "[]";
+
+    }
+
+