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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Copyright 2005-2010 Google, Inc.
// Author: jpr@google.com (Jake Ratkiewicz)
// Represents a generic weight in an FST -- that is, represents a specific
// type of weight underneath while hiding that type from a client.
#ifndef FST_SCRIPT_WEIGHT_CLASS_H_
#define FST_SCRIPT_WEIGHT_CLASS_H_
#include <string>
#include <fst/generic-register.h>
#include <fst/util.h>
namespace fst {
namespace script {
class WeightImplBase {
public:
virtual WeightImplBase *Copy() const = 0;
virtual void Print(ostream *o) const = 0;
virtual const string &Type() const = 0;
virtual string to_string() const = 0;
virtual bool operator == (const WeightImplBase &other) const = 0;
virtual ~WeightImplBase() { }
};
template<class W>
struct WeightClassImpl : public WeightImplBase {
W weight;
explicit WeightClassImpl(const W& weight) : weight(weight) { }
virtual WeightClassImpl<W> *Copy() const {
return new WeightClassImpl<W>(weight);
}
virtual const string &Type() const { return W::Type(); }
virtual void Print(ostream *o) const {
*o << weight;
}
virtual string to_string() const {
ostringstream s;
s << weight;
return s.str();
}
virtual bool operator == (const WeightImplBase &other) const {
if (Type() != other.Type()) {
return false;
} else {
const WeightClassImpl<W> *typed_other =
static_cast<const WeightClassImpl<W> *>(&other);
return typed_other->weight == weight;
}
}
};
class WeightClass {
public:
WeightClass() : element_type_(ZERO), impl_(0) { }
template<class W>
explicit WeightClass(const W& weight)
: element_type_(OTHER), impl_(new WeightClassImpl<W>(weight)) { }
WeightClass(const string &weight_type, const string &weight_str);
WeightClass(const WeightClass &other) :
element_type_(other.element_type_),
impl_(other.impl_ ? other.impl_->Copy() : 0) { }
WeightClass &operator = (const WeightClass &other) {
if (impl_) delete impl_;
impl_ = other.impl_ ? other.impl_->Copy() : 0;
element_type_ = other.element_type_;
return *this;
}
template<class W>
const W* GetWeight() const;
string to_string() const {
switch (element_type_) {
case ZERO:
return "ZERO";
case ONE:
return "ONE";
default:
case OTHER:
return impl_->to_string();
}
}
bool operator == (const WeightClass &other) const {
return element_type_ == other.element_type_ &&
((impl_ && other.impl_ && (*impl_ == *other.impl_)) ||
(impl_ == 0 && other.impl_ == 0));
}
static const WeightClass &Zero() {
static WeightClass w(ZERO);
return w;
}
static const WeightClass &One() {
static WeightClass w(ONE);
return w;
}
~WeightClass() { if (impl_) delete impl_; }
private:
enum ElementType { ZERO, ONE, OTHER };
ElementType element_type_;
WeightImplBase *impl_;
explicit WeightClass(ElementType et) : element_type_(et), impl_(0) { }
friend ostream &operator << (ostream &o, const WeightClass &c);
};
template<class W>
const W* WeightClass::GetWeight() const {
// We need to store zero and one as statics, because the weight type
// W might return them as temporaries. We're returning a pointer,
// and it won't do to get the address of a temporary.
static const W zero = W::Zero();
static const W one = W::One();
if (element_type_ == ZERO) {
return &zero;
} else if (element_type_ == ONE) {
return &one;
} else {
if (W::Type() != impl_->Type()) {
return NULL;
} else {
WeightClassImpl<W> *typed_impl =
static_cast<WeightClassImpl<W> *>(impl_);
return &typed_impl->weight;
}
}
}
//
// Registration for generic weight types.
//
typedef WeightImplBase* (*StrToWeightImplBaseT)(const string &str,
const string &src,
size_t nline);
template<class W>
WeightImplBase* StrToWeightImplBase(const string &str,
const string &src, size_t nline) {
return new WeightClassImpl<W>(StrToWeight<W>(str, src, nline));
}
// The following confuses swig, and doesn't need to be wrapped anyway.
#ifndef SWIG
ostream& operator << (ostream &o, const WeightClass &c);
class WeightClassRegister : public GenericRegister<string,
StrToWeightImplBaseT,
WeightClassRegister> {
protected:
virtual string ConvertKeyToSoFilename(const string &key) const {
return key + ".so";
}
};
typedef GenericRegisterer<WeightClassRegister> WeightClassRegisterer;
#endif
// internal version, needs to be called by wrapper in order for
// macro args to expand
#define REGISTER_FST_WEIGHT__(Weight, line) \
static WeightClassRegisterer weight_registerer ## _ ## line( \
Weight::Type(), \
StrToWeightImplBase<Weight>)
// This layer is where __FILE__ and __LINE__ are expanded
#define REGISTER_FST_WEIGHT_EXPANDER(Weight, line) \
REGISTER_FST_WEIGHT__(Weight, line)
//
// Macro for registering new weight types. Clients call this.
//
#define REGISTER_FST_WEIGHT(Weight) \
REGISTER_FST_WEIGHT_EXPANDER(Weight, __LINE__)
} // namespace script
} // namespace fst
#endif // FST_SCRIPT_WEIGHT_CLASS_H_
|
