Fast Dictionary Access

[Chris Rebert]

On Sat, Jun 27, 2009 at 2:47 AM, Thomas
Lehmann<Iris-und-Thomas-Lehmann at t-online.de> wrote:
> Hi!
>
> In C++, programming STL you will use the insert method which always
> provides a position and a flag which indicates whether the position
> results from a new insertion or an exisiting element. Idea is to have
> one search only.
>
> <code>
> if  data.has_key(key):
>   value = data[key]
> </code>
>
> But this does mean (does it?) that the dictionary is searched two
> times! If so, can somebody show me how to do this in one step?

Use exception handling:

try:
    value = data[key]
except KeyError:
    print "No such key"
else:
    print "The value for that key is", value

Cheers,
Chris
-- 
http://blog.rebertia.com