1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
|
// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// 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.
// Helper functions used for Unicode normalization
fn canonical_sort(comb: &mut [(char, u8)]) {
let len = comb.len();
for i in 0..len {
let mut swapped = false;
for j in 1..len-i {
let class_a = comb[j-1].1;
let class_b = comb[j].1;
if class_a != 0 && class_b != 0 && class_a > class_b {
comb.swap(j-1, j);
swapped = true;
}
}
if !swapped { break; }
}
}
#[derive(Clone)]
enum DecompositionType {
Canonical,
Compatible
}
/// External iterator for a string decomposition's characters.
#[derive(Clone)]
pub struct Decompositions<I> {
kind: DecompositionType,
iter: I,
buffer: Vec<(char, u8)>,
sorted: bool
}
#[inline]
pub fn new_canonical<I: Iterator<Item=char>>(iter: I) -> Decompositions<I> {
Decompositions {
iter: iter,
buffer: Vec::new(),
sorted: false,
kind: self::DecompositionType::Canonical,
}
}
#[inline]
pub fn new_compatible<I: Iterator<Item=char>>(iter: I) -> Decompositions<I> {
Decompositions {
iter: iter,
buffer: Vec::new(),
sorted: false,
kind: self::DecompositionType::Compatible,
}
}
impl<I: Iterator<Item=char>> Iterator for Decompositions<I> {
type Item = char;
#[inline]
fn next(&mut self) -> Option<char> {
use self::DecompositionType::*;
match self.buffer.first() {
Some(&(c, 0)) => {
self.sorted = false;
self.buffer.remove(0);
return Some(c);
}
Some(&(c, _)) if self.sorted => {
self.buffer.remove(0);
return Some(c);
}
_ => self.sorted = false
}
if !self.sorted {
for ch in self.iter.by_ref() {
let buffer = &mut self.buffer;
let sorted = &mut self.sorted;
{
let callback = |d| {
let class =
super::char::canonical_combining_class(d);
if class == 0 && !*sorted {
canonical_sort(buffer);
*sorted = true;
}
buffer.push((d, class));
};
match self.kind {
Canonical => {
super::char::decompose_canonical(ch, callback)
}
Compatible => {
super::char::decompose_compatible(ch, callback)
}
}
}
if *sorted {
break
}
}
}
if !self.sorted {
canonical_sort(&mut self.buffer);
self.sorted = true;
}
if self.buffer.is_empty() {
None
} else {
match self.buffer.remove(0) {
(c, 0) => {
self.sorted = false;
Some(c)
}
(c, _) => Some(c),
}
}
}
fn size_hint(&self) -> (usize, Option<usize>) {
let (lower, _) = self.iter.size_hint();
(lower, None)
}
}
|
