| // Copyright 2015 The Servo Project Developers. See the |
| // COPYRIGHT file at the top-level directory of this distribution. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| use crate::BidiClass; |
| |
| /// This is the return value of [`BidiDataSource::bidi_matched_opening_bracket()`]. |
| /// |
| /// It represents the matching *normalized* opening bracket for a given bracket in a bracket pair, |
| /// and whether or not that bracket is opening. |
| #[derive(Debug, Copy, Clone)] |
| pub struct BidiMatchedOpeningBracket { |
| /// The corresponding opening bracket in this bracket pair, normalized |
| /// |
| /// In case of opening brackets, this will be the bracket itself, except for when the bracket |
| /// is not normalized, in which case it will be the normalized form. |
| pub opening: char, |
| /// Whether or not the requested bracket was an opening bracket. True for opening |
| pub is_open: bool, |
| } |
| |
| /// This trait abstracts over a data source that is able to produce the Unicode Bidi class for a given |
| /// character |
| pub trait BidiDataSource { |
| fn bidi_class(&self, c: char) -> BidiClass; |
| /// If this character is a bracket according to BidiBrackets.txt, |
| /// return the corresponding *normalized* *opening bracket* of the pair, |
| /// and whether or not it itself is an opening bracket. |
| /// |
| /// This effectively buckets brackets into equivalence classes keyed on the |
| /// normalized opening bracket. |
| /// |
| /// The default implementation will pull in a small amount of hardcoded data, |
| /// regardless of the `hardcoded-data` feature. This is in part for convenience |
| /// (since this data is small and changes less often), and in part so that this method can be |
| /// added without needing a breaking version bump. |
| /// Override this method in your custom data source to prevent the use of hardcoded data. |
| fn bidi_matched_opening_bracket(&self, c: char) -> Option<BidiMatchedOpeningBracket> { |
| crate::char_data::bidi_matched_opening_bracket(c) |
| } |
| } |