describing how and when to override clone, and link to scope property

README.rst

@@ -24,7 +24,7 @@ then you can activate the virtual enviroment (in bash) and install the dependenc
 .. code:: shell
 
    source .venv/bin/activate
-   pip install -r requiremets.txt
+   pip install -r requirements.txt
 
 and then you can use ``make`` the usual way
 

source/SpinalHDL/Design errors/spinal_cant_clone.rst

@@ -8,8 +8,8 @@ Introduction
 This error happens when SpinalHDL wants to create a new datatype instance via the ``cloneOf`` function but isn't able to do it.
 The reason for this is nearly always because it can't retrieve the construction parameters of a ``Bundle``.
 
-Example
--------
+Example 1
+---------
 
 The following code:
 
@@ -47,3 +47,48 @@ A fix could be:
    class TopLevel extends Component {
      val tmp = Stream(RGB(8))
    }
+
+Example 2
+---------
+
+The following code:
+
+.. code-block:: scala
+
+  case class Xlen(val xlen: Int) {}
+
+  case class MemoryAddress()(implicit xlenConfig: Xlen) extends Bundle {
+      val address = UInt(xlenConfig.xlen bits)
+  }
+
+  class DebugMemory(implicit config: Xlen) extends Component {
+      val io = new Bundle {
+          val inputAddress = in(MemoryAddress())
+      }   
+
+      val someAddress = RegNext(io.inputAddress) // -> ERROR *****************************
+  }
+
+raises an exeption:
+
+.. code-block:: text
+
+  [error] *** Spinal can't clone class debug.MemoryAddress datatype
+
+In this case, a solution is to override the clone function to propagate the implicit parameter.
+
+.. code-block:: scala
+
+  case class MemoryAddress()(implicit xlenConfig: Xlen) extends Bundle {
+    val address = UInt(xlenConfig.xlen bits)
+
+    override def clone = MemoryAddress()
+  }
+
+.. note::
+
+  We need to clone the hardware element, not the eventually assigned value in it.
+
+.. note::
+
+  An alternative is to used :ref:`ScopeProperty <scopeproperty>`.

source/SpinalHDL/Other language features/scope_property.rst

@@ -1,3 +1,4 @@
+.. _scopeproperty:
 
 ScopeProperty
 ==================