1/*
2 * Copyright (C) 2010, Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#ifndef TextPosition_h
26#define TextPosition_h
27
28#include <wtf/Assertions.h>
29
30namespace WTF {
31
32// An abstract number of element in a sequence. The sequence has a first element.
33// This type should be used instead of integer because 2 contradicting traditions can
34// call a first element '0' or '1' which makes integer type ambiguous.
35class OrdinalNumber {
36public:
37 static OrdinalNumber fromZeroBasedInt(int zeroBasedInt) { return OrdinalNumber(zeroBasedInt); }
38 static OrdinalNumber fromOneBasedInt(int oneBasedInt) { return OrdinalNumber(oneBasedInt - 1); }
39 OrdinalNumber() : m_zeroBasedValue(0) { }
40
41 int zeroBasedInt() const { return m_zeroBasedValue; }
42 int oneBasedInt() const { return m_zeroBasedValue + 1; }
43
44 bool operator==(OrdinalNumber other) { return m_zeroBasedValue == other.m_zeroBasedValue; }
45 bool operator!=(OrdinalNumber other) { return !((*this) == other); }
46
47 static OrdinalNumber first() { return OrdinalNumber(0); }
48 static OrdinalNumber beforeFirst() { return OrdinalNumber(-1); }
49
50private:
51 OrdinalNumber(int zeroBasedInt) : m_zeroBasedValue(zeroBasedInt) { }
52 int m_zeroBasedValue;
53};
54
55
56// TextPosition structure specifies coordinates within an text resource. It is used mostly
57// for saving script source position.
58class TextPosition {
59public:
60 TextPosition(OrdinalNumber line, OrdinalNumber column)
61 : m_line(line)
62 , m_column(column)
63 {
64 }
65 TextPosition() { }
66 bool operator==(const TextPosition& other) { return m_line == other.m_line && m_column == other.m_column; }
67 bool operator!=(const TextPosition& other) { return !((*this) == other); }
68
69 // A 'minimum' value of position, used as a default value.
70 static TextPosition minimumPosition() { return TextPosition(OrdinalNumber::first(), OrdinalNumber::first()); }
71
72 // A value with line value less than a minimum; used as an impossible position.
73 static TextPosition belowRangePosition() { return TextPosition(OrdinalNumber::beforeFirst(), OrdinalNumber::beforeFirst()); }
74
75 OrdinalNumber m_line;
76 OrdinalNumber m_column;
77};
78
79}
80
81using WTF::OrdinalNumber;
82
83using WTF::TextPosition;
84
85#endif // TextPosition_h
86