RFC 9839: Defining Safer Unicode Character Subsets for Protocols and Data Structures
By
Bogdanp
Sesame, salt, and substance. A flagship bake.
Summary
RFC 9839 addresses the issue of which Unicode characters should be excluded from text fields in data structures and protocols, despite Unicode being generally beneficial. The authors explain why certain characters are problematic and propose three practical subsets for safer implementation.
Key quotes
· 3 pulledUnicode is good. If you're designing a data structure or protocol that has text fields, they should contain Unicode characters encoded in UTF-8.
There's another question, though: 'Which Unicode characters?' The answer is 'Not all of them, please exclude some.'
It explains which characters are bad, and why, then offers three plausible less-bad subsets that you might want to use.
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