On 16/06/16 16:38, boB Stepp wrote: > class FTPFiles(FTP, object): > """FTP files to Windows server location(s)."""
OK, First comment. You describe this as an action(verb) rather than a noun. Classes should represent nouns (objects) not actions. FTP represents a protocol connection with which you can do things (one of which is put/get files) you class should be the same. (Remember inheritance m,eans you are imp0lementing an "is a" relationship. So FTPFiles is an FTP...or should be.) > def __init__(self, host=server_ip, user=user, passwd=passwd): > """Initialize FTPFiles object. Normally the defaults will be used.""" > > super(FTPFiles, self).__init__(host, user, passwd) > self.host = host > self.user = user > self.passwd = passwd > > def print_welcome_msg(self): > """Print welcome message sent by FTP server.""" > print self.getwelcome() > 1) FTP from ftplib appears to be an old-style class. Using Python 2.4 that's not too surprising, FTP is an old module. > 4) I have to use "super(FTPFiles, self).__init__(host, user, passwd)" > or I cannot successfully inherit from the FTP() class. Also, "self" > apparently must come AFTER "FTPFiles" in the super expression. That's the v2 super(). v3 super is far supeerior. > 4) As this class stuff is mostly treading new ground for me, am I > doing anything that I should not be doing or should do in a more > preferred way? Keep in mind that I am just starting on this code > today. I'll leave someone with more ftplib experience to answer the other points but the question I'd ask is what are you planning to add to FTP? Creating a new class by inheritance implies that you are going to be extending (or specializing) its capabilities in some way. What are you planning to extend/specialize? For example are you going to limit it to manipulating files only? ie prevent listing directories say? You need to know what you are changing to warrant using inheritance. Inheritance is a powerful tool but it carries lots of potential for problems too, especially if you plan on mixing your new class in with the old one (or sharing it with others who will) - you need to be careful to abide by the Liskov substitution principle (LSP). -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ http://www.amazon.com/author/alan_gauld Follow my photo-blog on Flickr at: http://www.flickr.com/photos/alangauldphotos _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
