[Tutor] Merge a dictionary into a string

[Mats Wichmann]

On 3/16/19 11:39 AM, Valerio Pachera wrote:
> Consider this:
> 
> import collections
> d = OrderedDict(a='hallo', b='world')
> 
> I wish to get a single string like this:
> 
> 'a "hallo" b "world"'
> 
> Notice I wish the double quote to be part of the string.
> In other words I want to wrap the value of a and b.

So the question that comes to mind is "why"?  I don't mean that in the
negative sense as in you don't want to do that, but your use case may
drive the choice of possible solutions.

For example, I once got asked very nearly this question by someone who
it turned out wanted to serialize the dict into something that could
later be used to load up a dict. String is what he thought of, but in
this case json, or pickle, turned out to be a better solution for what
he wanted than a string.

If you only want to print the string for informational purposes, the
suggestions here will work well.  You can even define your own class
which inherits from OrderedDict and just provides a new definition of
the method which produces a string representation and gives you what you
want without calling anything, like this:

>>> class MyOrderedDict(OrderedDict):
...     def __repr__(self):
...         return " ".join(f'{k} "{v}"' for k, v in self.items())
...
>>>
>>> d = MyOrderedDict(a='hallo', b='world')
>>> print(d)
a "hallo" b "world"
>>> x = str(d)
>>> x
'a "hallo" b "world"'