Isolate _multibytecodec #103583
Description
Linked PRs
- gh-103583: Add codecs and maps to _codecs_* module state #103540
- gh-103583: Always pass multibyte codec structs as const #103588
- gh-103583: Add ref. dependency between multibytecodec modules #103589
- gh-103583: Isolate CJK modules, alternative 1 #103868
- gh-103583: Isolate CJK codec modules #103869
- gh-103583: Isolate CJK modules, alternative 3 #103870