Index: generic/tclBdd.c
==================================================================
--- generic/tclBdd.c
+++ generic/tclBdd.c
@@ -66,29 +66,66 @@
     do {			  \
 	++((x)->refCount);	  \
     } while(0)
 #define DecrBddSystemDataRefCount(x)		\
     do {					\
-	BddSystemData* sys = x;		\
-	if ((--(sys->refCount)) <= 0) {	\
+	BddSystemData* sys = (x);		\
+	if ((--(sys->refCount)) <= 0) {		\
 	    DeleteBddSystemData(sys);		\
 	}					\
     } while(0)
 
+/*
+ * Structure that represents a single bead (or a BDD) to TclOO
+ */
+
+typedef struct BddBeadData {
+    unsigned int refCount;	/* Reference count */
+    BddSystemData* sdata;	/* BDD system data */
+    unsigned int bead;		/* Bead index */
+} BddBeadData;
+#define IncrBddBeadDataRefCount(x) \
+    do {			   \
+        ++((x)->refCount);         \
+    } while(0)
+#define DecrBddBeadDataRefCount(x) 		\
+    do {					\
+        BddBeadData* bdata = (x);		\
+	if ((--(bdata->refCount)) <= 0) {	\
+	    DeleteBddBeadData(bdata);		\
+	}					\
+    } while(0)
+
 /*
  * Static functions defined within this file
  */
 
 static void DeletePerInterpData(PerInterpData*);
 
+static int BddBeadConstructor(ClientData, Tcl_Interp*, Tcl_ObjectContext,
+			      int, Tcl_Obj* const[]);
 static int BddSystemConstructor(ClientData, Tcl_Interp*, Tcl_ObjectContext,
 				int, Tcl_Obj* const[]);
+static int CloneBddBeadObject(Tcl_Interp*, ClientData, ClientData*);
 static int CloneBddSystemObject(Tcl_Interp*, ClientData, ClientData*);
 static int CloneMethod(Tcl_Interp*, ClientData, ClientData*);
+static void DeleteBddBeadData(BddBeadData*);
+static void DeleteBddBeadObject(ClientData);
 static void DeleteBddSystemData(BddSystemData*);
 static void DeleteBddSystemObject(ClientData);
 static void DeleteMethod(ClientData);
+
+/*
+ * TclOO data types defined within this file
+ */
+
+const static Tcl_ObjectMetadataType BddBeadDataType = {
+    TCL_OO_METADATA_VERSION_CURRENT, /* version */
+    "BddBeadData",		     /* name */
+    DeleteBddBeadObject,	     /* deleteProc */
+    CloneBddBeadObject		     /* cloneProc */
+};
 
 /*
  * TclOO data types defined within this file
  */
 
@@ -105,10 +142,18 @@
 
 const static Tcl_MethodType BddSystemConstructorType = {
     TCL_OO_METHOD_VERSION_CURRENT, /* version */
     "CONSTRUCTOR",		   /* name */
     BddSystemConstructor,	   /* callProc */
+    DeleteMethod,		   /* method delete proc */
+    CloneMethod			   /* method clone proc */
+};
+
+const static Tcl_MethodType BddSystemBeadConstructorType = {
+    TCL_OO_METHOD_VERSION_CURRENT, /* version */
+    "CONSTRUCTOR",		   /* name */
+    BddBeadConstructor,		   /* callProc */
     DeleteMethod,		   /* method delete proc */
     CloneMethod			   /* method clone proc */
 };
 
 /*
@@ -243,10 +288,12 @@
 	Tcl_SetErrorCode(interp, "BDD", "InitialSize<4",
 			 Tcl_GetString(objv[skip]), NULL);
 	return TCL_ERROR;
     }
 
+    Tcl_ObjectContextInvokeNext(interp, objectContext, skip, objv, skip);
+
     /* Create the BDD system */
 
     sdata = (BddSystemData*) ckalloc(sizeof(BddSystemData));
     sdata->refCount = 1;
     sdata->pidata = pidata;
@@ -254,10 +301,62 @@
     sdata->system = BDD_NewSystem(size);
     
     Tcl_ObjectSetMetadata(thisObject, &BddSystemDataType, (ClientData) sdata);
     return TCL_OK;
 }
+
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * BddBeadConstructor --
+ *
+ *	Constructs a bead in a Binary Decision Diagram.
+ *
+ * Parameters:
+ *	None.
+ *
+ * Results:
+ *	Returns a standard Tcl result.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+static int
+BddBeadConstructor(
+    ClientData clientData,	     /* Pointer to the per-interp data */
+    Tcl_Interp* interp,		     /* Tcl interpreter */
+    Tcl_ObjectContext objectContext, /* Object context */
+    int objc,			     /* Parameter count */
+    Tcl_Obj *const objv[]	     /* Parameter vector */
+) {
+    BddSystemData* sdata = (BddSystemData*) clientData;
+				/* Per-interp data for the BDD package */
+    Tcl_Object thisObject = Tcl_ObjectContextObject(objectContext);
+				/* Current object */
+    int skip = Tcl_ObjectContextSkippedArgs(objectContext);
+				/* Number of leading args to skip */
+    BddBeadData* bdata;
+    
+    /* Check arguments */
+
+    if (objc != skip) {
+	Tcl_WrongNumArgs(interp, skip, objv, "");
+	return TCL_ERROR;
+    }
+    Tcl_ObjectContextInvokeNext(interp, objectContext, skip, objv, skip);
+
+    /* Create the BDD system */
+
+    bdata = (BddBeadData*) ckalloc(sizeof(BddBeadData));
+    bdata->refCount = 1;
+    bdata->sdata = sdata;
+    bdata->bead = 0;
+    IncrBddSystemDataRefCount(sdata);
+    
+    Tcl_ObjectSetMetadata(thisObject, &BddBeadDataType, (ClientData) bdata);
+    return TCL_OK;
+}
 
 /*
  *-----------------------------------------------------------------------------
  *
  * CloneBddSystemObject --
@@ -334,10 +433,27 @@
     BDD_DeleteSystem(sdata->system);
     sdata->system = NULL;
     DecrPerInterpRefCount(sdata->pidata);
     ckfree(sdata);
 }
+
+/*
+ *-----------------------------------------------------------------------------
+ *
+ * DeleteBddBeadObject --
+ *
+ *	Cleans up when a bead in a BDD is deleted.
+ *
+ *-----------------------------------------------------------------------------
+ */
+
+void
+DeleteBddBeadObject(
+    ClientData clientData
+) {
+    DecrBddBeadDataRefCount((BddBeadData*) clientData);
+}
 
 /*
  *-----------------------------------------------------------------------------
  *
  * DeleteBddSystemObject --

Index: library/tclbdd.tcl
==================================================================
--- library/tclbdd.tcl
+++ library/tclbdd.tcl
@@ -11,7 +11,33 @@
 
 namespace eval bdd {
     namespace export system
 }
 
+oo::class create bdd::System {
+    variable beadseq
+    constructor args {
+	namespace eval Bead {}
+	set beadseq 0
+	bdd::bead create Bead::false [self]
+	bdd::bead create Bead::true [self]
+	Bead::true = 1
+    }
+    method false {} {
+	return [namespace which Bead::false]
+    }
+    method true {} {
+	return [namespace which Bead::true]
+    }
+}
 oo::class create bdd::system {
+    superclass bdd::System
+}
+
+oo::class create bdd::Bead {
+    constructor args {
+    }
+}
+
+oo::class create bdd::bead {
+    superclass bdd::Bead
 }