Question

Is there some kind of enumeration library or method I should use or should I write from scratch with recursion?

I’m parsing a JSON tree into an object tree as it happens, and I’d like to replace some nodes with other kinds of objects.

E.g:

db = {'bigBang' :
          {'stars':
               {'planets': {}, 'is_list':true
               }
           }
     }
db.deepReplace( 'is_list', ['earth', 'mars'] )
>> db is now: 
>> {'bigBang' :
>>        {'stars':
>>             {'planets':
>>                 {
>>                     ['earth', 'mars']
>>                 }
>>             }
>>         }
>> }

Answer 1

If you know there’s only one node to replace:

def deepReplace(d, key, value):
    if isinstance(d, dict):
        if key in d:
            d[key] = value
            return True
        else:
            for k,v in d.iteritems():
                if deepReplace(v, key, value):
                    return True
    return False

Otherwise:

def deepReplace(d, key, value):
    if isinstance(d, dict):
        if key in d:
            d[key] = value
        else:
            for k,v in d.iteritems():
                deepReplace(v, key, value):