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Re: Dictionary of Dicts question

On Thu, Oct 16, 2008 at 12:19 PM, John Townsend <jt******@adobe.comwrote:
I'm working with a Dictionary of Dicts. Something like this:

myDict = {
'TestName': {







Accessing values is pretty straightforward (nice change from my Perl days).
For example:


in Python interpreter yields


However, when I try to add, let's say, a new FileName entry, I end up
replacing the previous FileName entry.

In Python interpreter, I try:

myDict['TestName'] = {'NewFileName': {}, }

I get

{'TestName': {'NewFileName': {}}}
Right, this clobbers the existing entry with this new blank one. This
is evidenced by the fact that you're performing an _assignment_ on a
dictionary key rather than calling a _mutator_ method on a dictionary
value. A dictionary has only one value for a given key (but
importantly, that value can be a list).
So, how do I add a new entry without replacing the old entry?
Switch to a Dict of Lists of Dicts and append to the appropriate list
when adding the new entry, or preferably, start using objects instead
of ad-hoc nested dictionaries.

Follow the path of the Iguana...

John Townsend (5-7204),
AGM-FL and PSL QE Lead


Oct 16 '08 #1
0 911

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