Do Dictionaries have a key length limit?

Question

I was wondering if Python had a limit on the length of a dictionary key.

For clarification, I'm not talking about the number of keys, but the length of each individual key. I'm going to be building my dictionaries based on dynamic values (after validation), but I'm not sure if I should be taking length into account in this case.

Answer 1

There is no such limit in place regarding dictionary keys. Since python also has arbitrary precision on numeric types, the only limit you will encounter, string or otherwise, is that of available memory. You can see another post here for a discussion on maximum string length in python 2.

Answer 2

Here's a bit of sample code:

from string import ascii_letters from random import choice  def make_str(length):     return "".join(choice(ascii_letters) for i in range(length))  test_dict = {make_str(10000000): i for i in range(5)} 

Conclusion: Python will quite happily use a 10-million-character string as a dict key.