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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
//
// Token.h
//
// Library: Foundation
// Package: Streams
// Module: StreamTokenizer
//
// Definition of the Token class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Token_INCLUDED
#define Foundation_Token_INCLUDED
#include "Poco/Foundation.h"
#include <istream>
namespace Poco {
class Foundation_API Token
/// The base class for all token classes that can be
/// registered with the StreamTokenizer.
{
public:
enum Class
{
IDENTIFIER_TOKEN,
KEYWORD_TOKEN,
SEPARATOR_TOKEN,
OPERATOR_TOKEN,
STRING_LITERAL_TOKEN,
CHAR_LITERAL_TOKEN,
INTEGER_LITERAL_TOKEN,
LONG_INTEGER_LITERAL_TOKEN,
FLOAT_LITERAL_TOKEN,
DOUBLE_LITERAL_TOKEN,
COMMENT_TOKEN,
SPECIAL_COMMENT_TOKEN,
PREPROCESSOR_TOKEN,
WHITESPACE_TOKEN,
EOF_TOKEN,
INVALID_TOKEN,
USER_TOKEN
};
Token();
/// Creates the Token.
virtual ~Token();
/// Destroys the Token.
virtual bool start(char c, std::istream& istr);
/// Checks if the given character (and, optionally,
/// the next character in the input stream) start
/// a valid token. Returns true if so, false
/// otherwise.
///
/// The current read position in istr must not be
/// changed. In other words, only the peek() method
/// of istream may be used.
///
/// If the character starts the token, it should
/// be set as the token's value.
virtual void finish(std::istream& istr);
/// Builds the token by reading and appending
/// the remaining characters from istr.
virtual Class tokenClass() const;
/// Returns the kind of the token.
const std::string& tokenString() const;
/// Returns the token's raw string.
virtual std::string asString() const;
/// Returns a string representation of the token.
#if defined(POCO_HAVE_INT64)
virtual Int64 asInteger64() const;
/// Returns a 64-bit integer representation of the token.
virtual UInt64 asUnsignedInteger64() const;
/// Returns an unsigned 64-bit integer representation of the token.
#endif
virtual int asInteger() const;
/// Returns an integer representation of the token.
virtual unsigned asUnsignedInteger() const;
/// Returns an unsigned integer representation of the token.
virtual double asFloat() const;
/// Returns a floating-point representation of the token.
virtual char asChar() const;
/// Returns a char representation of the token.
bool is(Class tokenClass) const;
/// Returns true iff the token has the given class.
protected:
std::string _value;
private:
Token(const Token&);
Token& operator = (const Token&);
};
class Foundation_API InvalidToken: public Token
/// This token class is used for signalling that
/// an invalid character sequence has been encountered
/// in the input stream.
{
public:
InvalidToken();
~InvalidToken();
Class tokenClass() const;
};
class Foundation_API EOFToken: public Token
/// This token class is used to signal the
/// end of the input stream.
{
public:
EOFToken();
~EOFToken();
Class tokenClass() const;
};
class Foundation_API WhitespaceToken: public Token
/// This pseudo token class is used to eat
/// up whitespace in between real tokens.
{
public:
WhitespaceToken();
~WhitespaceToken();
Class tokenClass() const;
bool start(char c, std::istream& istr);
void finish(std::istream& istr);
};
//
// inlines
//
inline const std::string& Token::tokenString() const
{
return _value;
}
inline bool Token::is(Token::Class cls) const
{
return tokenClass() == cls;
}
} // namespace Poco
#endif // Foundation_Token_INCLUDED
|
