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Add ASCII fast-path for char::is_grapheme_extended #121138

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Mar 5, 2024
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Add ASCII fast-path for char::is_grapheme_extended #121138

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2 changes: 1 addition & 1 deletion library/core/src/char/methods.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -927,7 +927,7 @@ impl char {
#[must_use]
#[inline]
pub(crate) fn is_grapheme_extended(self) -> bool {
unicode::Grapheme_Extend(self)
self > '\x7f' && unicode::Grapheme_Extend(self)
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@tgross35 tgross35 Mar 5, 2024 •
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Any reason not to instead update unicode-table-generator so this becomes a part of Grapheme_Extend (unicode::unicode_data::grapheme_extended::lookup)? So as to help anywhere else this call might wind up getting used

Doesn't have to be part of this PR, maybe later refactoring

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We really should have a const ASCII_MAX: char = '\x7f' somewhere, maybe even public. We throw that magic number around a lot

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The generator doesn't know specifics about particular properties yet, AFAICS, but I could imagine it could generically optimize lookups outside of a property's min/max.

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I actually did this in the unicode-table-generator (and fun fact: this was the only properly with a min > ASCII). Let me open that up as a PR.

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Here you go: #122013

}

/// Returns `true` if this `char` has one of the general categories for numbers.
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