def _inform_cannot_edit_no_custom_dir():
    """
    Inform the user that a custom dir has not be specified, and thus an edit
    cannot be performed.
    """
    msg = """
    You've requested to edit custom examples for a command, but no custom
    directory has been found. The value must be set and the directory must
    exist.

    Custom examples are shown before the default examples and are under your
    control. You must specify where to save them before editing them. This can
    be done at the command line (with the `-c` or `--custom-dir` flags) or via
    the `custom-dir` option in your egrc. A minimal egrc might look like:

    [eg-config]
    custom-dir = ~/.eg/
    """
    print(msg)

    Inform the user that a custom dir has not be specified, and thus an edit
    cannot be performed.
    
eg/util.py