Jean-Paul Calderone wrote: > On Fri, 06 Jul 2007 15:43:55 -0000, Robert Dailey <[EMAIL PROTECTED]> wrote: >> Hi, >> >> I am interested in creating an expandable (dynamic) 2D dictionary. For >> example: >> >> myvar["cat"]["paw"] = "Some String" >> >> The above example assumes "myvar" is declared. In order for this to >> work, I have to know ahead of time the contents of the dictionary. For >> the above to work, my declaration must look like: >> >> myvar = {"cat": {"paw":""} } >> >> I would like to not have to declare my dictionary like this, as it >> does not allow it to be expandable. I'm very new to Python (I'm a >> professional C++ programmer. Any comparisons to C++ would help me >> understand concepts). >> >> Is there a way that when I index into my dictionary using an "unknown" >> index (string), that python will dynamically add that key/value pair? > > This gets much easier if you change your structure around a bit: > > d = {} > d["cat", "paw"] = "some string" > > Jean-Paul
Unfortunately that makes it somewhat more difficult to retrieve the set of entries whose first index is "cat". I realise that we don't have much in the way of use cases here, but it would seem that the original motivation for a two-level dictionary might have been such a requirement. regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 Holden Web LLC/Ltd http://www.holdenweb.com Skype: holdenweb http://del.icio.us/steve.holden --------------- Asciimercial ------------------ Get on the web: Blog, lens and tag the Internet Many services currently offer free registration ----------- Thank You for Reading ------------- -- http://mail.python.org/mailman/listinfo/python-list