named_axis: improve doc string of _prettify_named_axes

src/awkward/_namedaxis.py

@@ -47,15 +47,15 @@ def _prettify_named_axes(
  maxlen: None | int = None,
 ) -> str:
  """
- Prettifies the named axes for better readability.
-
  This function takes a named axis mapping and returns a string representation of the mapping.
  The axis names are sorted in ascending order of their corresponding integer values.
  If the axis name is a valid Python identifier, it is represented as is.
  Otherwise, it is represented as a JSON string.
 
  Args:
  named_axis (AxisMapping): The named axis mapping to prettify.
+ delimiter (str, optional): The delimiter to use between items in the output string. Defaults to ", ".
+ maxlen (None | int, optional): The maximum length of the output string. If the string exceeds this length, it is truncated and ends with "...". Defaults to None.
 
  Returns:
  str: The prettified string representation of the named axis mapping.
@@ -65,6 +65,10 @@ def _prettify_named_axes(
  'x:0, y:1, z:2'
  >>> _prettify_named_axes({"x": 0, "y": 1, "$": 2})
  'x:0, y:1, "$":2'
+ >>> _prettify_named_axes({"x": 0, "y": 1, "z": 2}, delimiter="; ")
+ 'x:0; y:1; z:2'
+ >>> _prettify_named_axes({"foo": 0, "bar": 1, "baz": 2}, maxlen=17)
+ 'foo:0, bar:1, ...'
  """
 
  def _prettify(ax: AxisName) -> str: