Question

I made a Python function to convert dictionaries to formatted strings. My goal was to have a function take a dictionary for input and turn it into a string that looked good. For example, something like {'text':'Hello', 'blah':{'hi':'hello','hello':'hi'}} would be turned into this:

text:
    Hello
blah:
    hi:
        hello
    hello:
        hi

This is the code I wrote:

indent = 0

def format_dict(d):
    global indent
    res = ""
    for key in d:
        res += ("   " * indent) + key + ":\n"
        if not type(d[key]) == type({}):
            res += ("   " * (indent + 1)) + d[key] + "\n"
        else:
            indent += 1
            res += format_dict(d[key])
            indent -= 1
    return res
#test
print format_dict({'key with text content':'some text', 
                  'key with dict content':
                  {'cheese': 'text', 'item':{'Blah': 'Hello'}}})

It works like a charm. It checks if the dictionary’s item is another dictionary, in which case it process that, or something else, then it would use that as the value. The problem is: I can’t have a dictionary and a string together in a dictionary item. For example, if I wanted:

blah:
    hi
    hello:
        hello again

there’d be no way to do it. Is there some way I could have something like a list item in a dictionary. Something like this {'blah':{'hi', 'hello':'hello again'}}? And if you provide a solution could you tell me how I would need to change my code (if it did require changes).
Note: I am using python 2.5

Answer 1

You can simply store a list in the dictionary. Also, it’s better not to use a global to store the indentation. Something along the lines of:

def format_value(v, indent):
    if isinstance(v, list):
         return ''.join([format_value(item, indent) for item in v])
    elif isinstance(v, dict):
         return format_dict(v, indent)
    elif isinstance(v, str):
         return ("   " * indent) + v + "\n"

def format_dict(d, indent=0):
    res = ""
    for key in d:
        res += ("   " * indent) + key + ":\n"
        res += format_value(d[key], indent + 1)
    return res