protected AudibleFileStorage(FileType fileType) : base((int)fileType, fileType.ToString())
{
extensions_noDots = Extensions.Select(ext => ext.Trim('.')).ToList();
extAggr = extensions_noDots.Aggregate((a, b) => $"{a}|{b}");
}
private AudibleFileStorage(FileType fileType, string storageDirectory, params string[] extensions) : base((int)fileType, storageDirectory)
{
extensions_noDots = extensions.Select(ext => ext.Trim('.')).ToList();
extAggr = extensions_noDots.Aggregate((a, b) => $"{a}|{b}");
}