[DISCUSSION] Limit of code point for grapheme cluster in programming languages

Hi, Internals I noticed grapheme cluster is not limit code points in UAX#29. https://www.unicode.org/reports/tr29/ And there is no limit code point in Unicode that confirmed in issue of ICU. https://unicode-org.atlassian.net/browse/ICU-23302 So that means create many code points in 1 grapheme cluster, That is crash for program because computer resource is limited. For example, this code is 200MB but 1 grapheme cluster in emoji_bomb.txt ``` php -r 'echo(mb_trim(str_repeat("\u{200d}\u{1f468}\u{200d}\u{1f466}\u {200d}\u{1f466}", 10000000), "\u{200d}"));' -d memory_limit=600M > emoji_bomb.txt ``` (PLEASE BE CAREFUL OPEN IN emoji_bomb.txt BECAUSE MAYBE CRASH) So, I think we(php-src, programming language level) need to create new custom limit function. My idea is below: ``` grapheme_limit_codepoints(string $str, integer $max_codepoints = 32): bool ``` I don't have heavy opinion that $max_codepoints is 32. However, 32 code points is enough of grapheme cluster because human language max code points is maybe Hakṣhmalawarayaṁ(ཧྐྵྨླྺྼྻྂ) in 9 code points. If need more than code points in grapheme cluster, Userland can to increase $max_codepoints. Please see also my speakerdeck. https://speakerdeck.com/youkidearitai/limit-of-code-point-for-grapheme-cluster What do you think about this idea? Regards Yuya -- --------------------------- Yuya Hamada (tekimen) - https://tekitoh-memdhoi.info - https://github.com/youkidearitai -----------------------------