2017-02-28 13:17 GMT+01:00 Michel Desmoulin <desmoulinmichel@gmail.com>:
We have the immutable frozenset for sets and and tuples for lists.
But we also have something to manipulate dict as immutable datastructures:
from types import MappingProxyType as idict d = idict({'a':1, 'b':2, 'c':3}) d['a'] = 4 Traceback (most recent call last): File "<ipython-input-3-c6f93d6278af>", line 1, in <module> d['a'] = 4 TypeError: 'mappingproxy' object does not support item assignment
We could expose this as a built type to allow the last of the most important data structure in Python to be easily immutable.
Hello, Such builtin type exists! It's called types.MappingProxyType! ... Sorry, I don't understand your proposition. Do you want to not have to write "from types import MappingProxyType" and put a new type in __builtins__? If yes, I don't think that it's worth it, it's not that hard to add an import to each file using such type. By the way, try to not abuse this type please ;-) (Don't try to put it everywhere?) Victor