Improve performance of std.stripChars and std.trim functions #555
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…using regular expressions
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#560) This is a followup to #555 and the subsequent fix in #557. Even after that fix, there are two remaining bugs related to stripping from the right side of a string: 1. Stripping emoji from end: `std.rstripChars("hello🎉🎉🎉", "🎉")` returned `"hello🎉🎉🎉"` instead of `"hello"` (nothing stripped) 2. Stripping ASCII after emoji: `std.trim("🌍 ")` returned `"?"` instead of`"🌍"` (i.e. the emoji was corrupted) The root cause (explained by Claude) is that when iterating from the right of a string, `codePointAt(str.length - 1)` points to a low surrogate and it gets treated as an unpaired surrogate rather than seeking backwards to find the full code point. The fix: use `codePointBefore(end)` (where `end` ranges from `string.length` down to `1`) for right-to-left iteration. Unlike `codePointAt()`, `codePointBefore()` correctly reads surrogate pairs when scanning backwards. Fix + test are authored by Claude Code. Co-authored-by: Claude <noreply@anthropic.com>
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Remove regular expressions usage - it's an overkill. Before: ``` [1-113] Java HotSpot(TM) 64-Bit Server VM warning: -XX:ThreadPriorityPolicy=1 may require system level permission, e.g., being the root user. If the necessary permission is not possessed, changes to priority will be silently ignored. 0.943 ms/op 0.761 ms/op ``` After: ``` [1-113] Java HotSpot(TM) 64-Bit Server VM warning: -XX:ThreadPriorityPolicy=1 may require system level permission, e.g., being the root user. If the necessary permission is not possessed, changes to priority will be silently ignored. 0.790 ms/op 0.674 ms/op ```
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Remove regular expressions usage - it's an overkill.
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