38 lines
1.3 KiB
Rust
38 lines
1.3 KiB
Rust
// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
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// file at http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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// (This used to be in the Rust unicode crate, which is now gone, so we'll
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// just include it inline.)
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// https://tools.ietf.org/html/rfc3629
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static UTF8_CHAR_WIDTH: [u8; 256] = [
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x1F
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x3F
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x5F
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
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1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // 0x7F
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0x9F
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
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0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 0xBF
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0,0,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
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2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // 0xDF
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3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3, // 0xEF
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4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0, // 0xFF
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];
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/// Given a first byte, determine how many bytes are in this UTF-8 character
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#[inline]
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pub fn utf8_char_width(b: u8) -> usize {
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return UTF8_CHAR_WIDTH[b as usize] as usize;
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}
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