Ron Phillips wrote: > Maybe I should explain why I thought I wanted this object. I am trying > to read, edit, and write shapefiles (actually, a shapefile is a > collection of 3-6 files having the same filename, but different > extensions. It's a legacy format that still gets a lot of use in > geography.) > > One of the constituent files in a shapefile is a variant of Xbase, > which knows nothing about NULL, so I have to provide some value in > every column for every record when I write them. I thought that having a > data structure that enforces a common set of "fields", the application > would be more robust when it's being edited. (Prevent me from deleting > an item for one record and not others, or adding a field to a record > without adding at least some default value to all the others.) > > I just thought about it, but a CSV file has kind of the same problem.
I think I would try the same solution used by csv.DictWriter - use a writer object that has knowledge of the required fields and a default value. This assumes that at the time of writing you know what the required fields are, which seems reasonable but without knowing more about your app I can't be sure. Then the writer fills in the necessary default values as it writes the data. Kent _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
