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
|
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build ignore
package main
// Class is the Unicode BiDi class. Each rune has a single class.
type Class uint
const (
L Class = iota // LeftToRight
R // RightToLeft
EN // EuropeanNumber
ES // EuropeanSeparator
ET // EuropeanTerminator
AN // ArabicNumber
CS // CommonSeparator
B // ParagraphSeparator
S // SegmentSeparator
WS // WhiteSpace
ON // OtherNeutral
BN // BoundaryNeutral
NSM // NonspacingMark
AL // ArabicLetter
Control // Control LRO - PDI
numClass
LRO // LeftToRightOverride
RLO // RightToLeftOverride
LRE // LeftToRightEmbedding
RLE // RightToLeftEmbedding
PDF // PopDirectionalFormat
LRI // LeftToRightIsolate
RLI // RightToLeftIsolate
FSI // FirstStrongIsolate
PDI // PopDirectionalIsolate
unknownClass = ^Class(0)
)
var controlToClass = map[rune]Class{
0x202D: LRO, // LeftToRightOverride,
0x202E: RLO, // RightToLeftOverride,
0x202A: LRE, // LeftToRightEmbedding,
0x202B: RLE, // RightToLeftEmbedding,
0x202C: PDF, // PopDirectionalFormat,
0x2066: LRI, // LeftToRightIsolate,
0x2067: RLI, // RightToLeftIsolate,
0x2068: FSI, // FirstStrongIsolate,
0x2069: PDI, // PopDirectionalIsolate,
}
// A trie entry has the following bits:
// 7..5 XOR mask for brackets
// 4 1: Bracket open, 0: Bracket close
// 3..0 Class type
const (
openMask = 0x10
xorMaskShift = 5
)
|