The auto-register can now be turned on and off after the registry is …

…initialized.

README.md

@@ -69,7 +69,27 @@ assert registry.find("my_device") is the_device
 ```
 
 This greedy behavior can be suppressed with the *auto_register*
-parameter. If *auto_register* is false, then a device class can be
+parameter. It can also be turned off after initialization by setting
+the *auto_register* attribute to ``False``::
+
+```python
+
+registry = Registry(auto_register=False)
+
+# Make a bunch of devices
+...
+
+# Turn if off for this one
+registry.auto_register = False
+device = MyDevice(...)
+registry.auto_register = True
+
+# Register some other devices maybe
+...
+
+```
+
+If *auto_register* is false, then a device class can be
 decorated to allow the registry to find it:
 
 ```python

pyproject.toml

@@ -19,7 +19,7 @@ dependencies = ["ophyd"]
 
 [project.optional-dependencies]
 
-dev = ["black", "isort", "pytest", "build", "twine", "flake8", "caproto", "ruff"]
+dev = ["black", "isort", "pytest", "build", "twine", "flake8", "ruff"]
 
 [project.urls]
 "Homepage" = "https://github.com/spc-group/ophyd-registry"

src/ophydregistry/registry.py

@@ -107,6 +107,7 @@ class Registry:
     """
 
     use_typhos: bool = False
+    _auto_register: bool
 
     # components: Sequence
     _objects_by_name: Mapping
@@ -119,11 +120,28 @@ def __init__(self, auto_register: bool = True, use_typhos: bool = False):
         # Set up empty lists and things for registering components
         self.clear()
         self.use_typhos = use_typhos
-        # Add a callback to get notified of new objects
-        if auto_register:
+        self.auto_register = auto_register
+
+    @property
+    def auto_register(self):
+        return self._auto_register
+
+    @auto_register.setter
+    def auto_register(self, val):
+        """Turn on or off the automatic registration of new devices."""
+        self._auto_register = val
+        if val:
+            # Add a callback to get notified of new objects
             ophydobj.OphydObject.add_instantiation_callback(
                 self.register, fail_if_late=False
             )
+        else:
+            try:
+                ophydobj.OphydObject._OphydObject__instantiation_callbacks.remove(
+                    self.register
+                )
+            except ValueError:
+                pass
 
     def __getitem__(self, key):
         """Retrieve the object from the dicionary.
@@ -454,11 +472,14 @@ def register(self, component: ophydobj.OphydObject) -> ophydobj.OphydObject:
             # (Needed for some sub-components that are just readback
             # values of the parent)
             # Check that we're not adding a duplicate component name
+            if name == "I0_center":
+                print(self._objects_by_name.keys(), self)
             if name in self._objects_by_name.keys():
                 old_obj = self._objects_by_name[name]
                 is_readback = component in [
                     getattr(old_obj, "readback", None),
                     getattr(old_obj, "user_readback", None),
+                    getattr(old_obj, "val", None),
                 ]
                 if is_readback:
                     msg = f"Ignoring readback with duplicate name: '{name}'"