←back to thread

A “frozen” dictionary for Python

(lwn.net)
191 points jwilk | 1 comments | 11 Dec 25 09:51 UTC | HN request time: 1.598s | source
Show context
rurban ◴[11 Dec 25 16:27 UTC] No.46233434[source]▶
> so having a safe way to share dictionaries between threads will be a boon

Since only the keys are const, the values not, frozendict is not thread-safe per se. There needs to be a small lock around the value getter and setter.

replies(1): >>46233744 #
1. varelaz ◴[11 Dec 25 16:48 UTC] No.46233744[source]▶
it's thread safe on operations on the dict but not on the values. Same relates to other immutable structures like tuples. Lock will not help here cause unsafety comes from operation on value after value is obtained.