How to create a blank object, e.g. a list, using the namespace encoded in a string?

Question

I want to convert strings into blank list objects, which can then be updated/appended. How do I do this / can it even be done?

Imagine I have a string, 'blah'. I want to change this string, so that 'blah' becomes the object name of a blank list. In other words:

'blah'

def some_function('blah'):
   ...
   ...
   return(blah)

some_function(blah)

OUTPUT: blah = []

I know that if I pass

list('blah')

this returns

['b','l','a','h']

But instead I want the opposite, where

list('blah')

returns

blah = []

If someone says you can do it with `exec` or `compile` - DON'T - it's a terrible idea — rdas, Apr 18 '19 at 11:10
Even if you could create a name `blah` within the namespace of `somefunction()` (which you can, albeit not in a nice way) it still would have no effect on the namespace from which `somefunction()` was called. What is it you're trying to achieve? — brunns, Apr 18 '19 at 11:13

score 0 · Answer 1 · answered Apr 18 '19 at 11:20

Moving on from the comments, a more logical way out could be to use a dict:

d = {}                         # empty dict

s = 'blah'                     # str
d[s] = []                      # empty list with the name of the str, blah = []

d[s].append("hello there!")    # appending to `blah`
print(d[s])

score 0 · Answer 2 · answered Apr 18 '19 at 11:21

0

You can't in any meaningful way. I'd suggest heeding @Mark Tolonen's advice and using a dictionary like so:

dictionary = {}
dictionary['blah'] = []

If you'd now like to add to 'blah', you can use append():

dictionary['blah'].append(x)

answered Apr 18 '19 at 11:21

Alec

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How to create a blank object, e.g. a list, using the namespace encoded in a string?

2 Answers2