Allow redefining node anchors

README.md

@@ -250,6 +250,9 @@ elements:
 
 ![lovelace_gen](https://user-images.githubusercontent.com/1299821/62565373-ecd4ac80-b886-11e9-9dcb-c41b43027b2b.png)
 
+## Hidden bonus
+With lovelace_gen installed, you'll be able to redefine node anchors in the same file. A feature in the YAML specification, but an error in the engine Home Assistant normally uses...
+
 # FAQ
 
 ### How can I do global variables?

custom_components/lovelace_gen/__init__.py

@@ -65,3 +65,28 @@ def _uncache_file(ldr, node):
 async def async_setup(hass, config):
     llgen_config.update(config.get("lovelace_gen"));
     return True
+
+# Allow redefinition of node anchors
+import yaml
+
+def compose_node(self, parent, index):
+    if self.check_event(yaml.events.AliasEvent):
+        event = self.get_event()
+        anchor = event.anchor
+        if anchor not in self.anchors:
+            raise yaml.composer.ComposerError(None, None, "found undefined alias %r"
+                    % anchor, event.start_mark)
+        return self.anchors[anchor]
+    event = self.peek_event()
+    anchor = event.anchor
+    self.descend_resolver(parent, index)
+    if self.check_event(yaml.events.ScalarEvent):
+        node = self.compose_scalar_node(anchor)
+    elif self.check_event(yaml.events.SequenceStartEvent):
+        node = self.compose_sequence_node(anchor)
+    elif self.check_event(yaml.events.MappingStartEvent):
+        node = self.compose_mapping_node(anchor)
+    self.ascend_resolver()
+    return node
+
+yaml.composer.Composer.compose_node = compose_node