Small fixes in docstrings and documentation.

confz/confz_source.py

@@ -89,7 +89,7 @@ class ConfZCLArgSource(ConfZSource):
     """Certain command line arguments can be mapped to config arguments with a different
     name. The map does not need to include the two dashes at the beginning."""
     nested_separator: str = "."
-    """Separator will be used in nested environment variables."""
+    """Separator will be used in nested command line arguments."""
 
 
 @dataclass

confz/loaders/loader.py

@@ -29,7 +29,7 @@ def update_dict_recursively(cls, original_dict: Dict, update_dict: Dict):
 
     @classmethod
     def transform_nested_dicts(
-        cls, dict_in: Dict[str, Any], separator: str
+        cls, dict_in: Dict[str, Any], separator: str = "."
     ) -> Dict[str, Any]:
         """Transform dictionaries into nested dictionaries, using a separator in the
         keys as hint.

docs/source/usage/sources_loaders.rst

@@ -18,7 +18,7 @@ There are multiple config sources which support a heterogeneous set of use-cases
   select the corresponding variables with allow- and deny-lists and with an optional prefix and optional custom separator for nested variables. The variable names are
   either inferred from the config name or can be explicitly mapped.
 - :class:`~confz.ConfZCLArgSource` allows to load config data from command line arguments. An optional prefix allows
-  to select only parts of the arguments. Optional custom separator for nested variables is also supported. The argument names are either inferred from the config name or can be
+  to select only parts of the arguments. Optional custom separator for nested command line arguments is also supported. The argument names are either inferred from the config name or can be
   explicitly mapped.
 - :class:`~confz.ConfZDataSource` allows to define constant config data. This can be very useful for unit tests, see
   :ref:`context_manager`.