From Jason Turner

[stringbuf]

C++14 → C++17 9.5 KB 97 lines
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Archived: C++14 | C++17
Markdown: C++14 | C++17
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  1. tmp/tmpvtpsplw2/{from.md → to.md} +44 -43
tmp/tmpvtpsplw2/{from.md → to.md} RENAMED
@@ -4,49 +4,48 @@
4
  namespace std {
5
  template <class charT, class traits = char_traits<charT>,
6
  class Allocator = allocator<charT>>
7
  class basic_stringbuf : public basic_streambuf<charT, traits> {
8
  public:
9
- typedef charT char_type;
10
- typedef typename traits::int_type int_type;
11
- typedef typename traits::pos_type pos_type;
12
- typedef typename traits::off_type off_type;
13
- typedef traits traits_type;
14
- typedef Allocator allocator_type;
15
 
16
- // [stringbuf.cons] Constructors:
17
- explicit basic_stringbuf(ios_base::openmode which
18
- = ios_base::in | ios_base::out);
19
- explicit basic_stringbuf
20
- (const basic_string<charT,traits,Allocator>& str,
21
  ios_base::openmode which = ios_base::in | ios_base::out);
22
  basic_stringbuf(const basic_stringbuf& rhs) = delete;
23
  basic_stringbuf(basic_stringbuf&& rhs);
24
 
25
- // [stringbuf.assign] Assign and swap:
26
  basic_stringbuf& operator=(const basic_stringbuf& rhs) = delete;
27
  basic_stringbuf& operator=(basic_stringbuf&& rhs);
28
  void swap(basic_stringbuf& rhs);
29
 
30
- // [stringbuf.members] Get and set:
31
  basic_string<charT, traits, Allocator> str() const;
32
  void str(const basic_string<charT, traits, Allocator>& s);
33
 
34
  protected:
35
- // [stringbuf.virtuals] Overridden virtual functions:
36
- virtual int_type underflow();
37
- virtual int_type pbackfail(int_type c = traits::eof());
38
- virtual int_type overflow (int_type c = traits::eof());
39
- virtual basic_streambuf<charT,traits>* setbuf(charT*, streamsize);
40
 
41
-
42
- virtual pos_type seekoff(off_type off, ios_base::seekdir way,
43
  ios_base::openmode which
44
- = ios_base::in | ios_base::out);
45
- virtual pos_type seekpos(pos_type sp,
46
  ios_base::openmode which
47
- = ios_base::in | ios_base::out);
48
 
49
  private:
50
  ios_base::openmode mode; // exposition only
51
  };
52
 
@@ -68,22 +67,23 @@ For the sake of exposition, the maintained data is presented here as:
68
  read, and `out` set if the output sequence can be written.
69
 
70
  #### `basic_stringbuf` constructors <a id="stringbuf.cons">[[stringbuf.cons]]</a>
71
 
72
  ``` cpp
73
- explicit basic_stringbuf(ios_base::openmode which =
74
- ios_base::in | ios_base::out);
75
  ```
76
 
77
  *Effects:* Constructs an object of class `basic_stringbuf`, initializing
78
  the base class with `basic_streambuf()` ([[streambuf.cons]]), and
79
  initializing `mode` with `which`.
80
 
81
- `str() == ""`.
82
 
83
  ``` cpp
84
- explicit basic_stringbuf(const basic_string<charT,traits,Allocator>& s,
 
85
  ios_base::openmode which = ios_base::in | ios_base::out);
86
  ```
87
 
88
  *Effects:* Constructs an object of class `basic_stringbuf`, initializing
89
  the base class with `basic_streambuf()` ([[streambuf.cons]]), and
@@ -138,11 +138,11 @@ void swap(basic_stringbuf& rhs);
138
  template <class charT, class traits, class Allocator>
139
  void swap(basic_stringbuf<charT, traits, Allocator>& x,
140
  basic_stringbuf<charT, traits, Allocator>& y);
141
  ```
142
 
143
- *Effects:* `x.swap(y)`.
144
 
145
  #### Member functions <a id="stringbuf.members">[[stringbuf.members]]</a>
146
 
147
  ``` cpp
148
  basic_string<charT, traits, Allocator> str() const;
@@ -151,11 +151,11 @@ basic_string<charT,traits,Allocator> str() const;
151
  *Returns:* A `basic_string` object whose content is equal to the
152
  `basic_stringbuf` underlying character sequence. If the
153
  `basic_stringbuf` was created only in input mode, the resultant
154
  `basic_string` contains the character sequence in the range \[`eback()`,
155
  `egptr()`). If the `basic_stringbuf` was created with
156
- `which & ios_base::out` being true then the resultant `basic_string`
157
  contains the character sequence in the range \[`pbase()`, `high_mark`),
158
  where `high_mark` represents the position one past the highest
159
  initialized character in the buffer. Characters can be initialized by
160
  writing to the stream, by constructing the `basic_stringbuf` with a
161
  `basic_string`, or by calling the `str(basic_string)` member function.
@@ -172,31 +172,31 @@ void str(const basic_string<charT,traits,Allocator>& s);
172
 
173
  *Effects:* Copies the content of `s` into the `basic_stringbuf`
174
  underlying character sequence and initializes the input and output
175
  sequences according to `mode`.
176
 
177
- *Postconditions:* If `mode & ios_base::out` is true, `pbase()` points to
178
- the first underlying character and `epptr()` `>= pbase() + s.size()`
179
- holds; in addition, if `mode & ios_base::ate` is true,
180
  `pptr() == pbase() + s.size()` holds, otherwise `pptr() == pbase()` is
181
- true. If `mode & ios_base::in` is true, `eback()` points to the first
182
- underlying character, and both `gptr() == eback()` and
183
  `egptr() == eback() + s.size()` hold.
184
 
185
  #### Overridden virtual functions <a id="stringbuf.virtuals">[[stringbuf.virtuals]]</a>
186
 
187
  ``` cpp
188
- int_type underflow();
189
  ```
190
 
191
  *Returns:* If the input sequence has a read position available, returns
192
  `traits::to_int_type(*gptr())`. Otherwise, returns `traits::eof()`. Any
193
  character in the underlying buffer which has been initialized is
194
  considered to be part of the input sequence.
195
 
196
  ``` cpp
197
- int_type pbackfail(int_type c = traits::eof());
198
  ```
199
 
200
  *Effects:* Puts back the character designated by `c` to the input
201
  sequence, if possible, in one of three ways:
202
 
@@ -215,11 +215,11 @@ sequence, if possible, in one of three ways:
215
 
216
  *Remarks:* If the function can succeed in more than one of these ways,
217
  it is unspecified which way is chosen.
218
 
219
  ``` cpp
220
- int_type overflow(int_type c = traits::eof());
221
  ```
222
 
223
  *Effects:* Appends the character designated by `c` to the output
224
  sequence, if possible, in one of two ways:
225
 
@@ -245,11 +245,11 @@ plus at least one additional write position. If
245
  `egptr()` to point just past the new write position.
246
 
247
  ``` cpp
248
  pos_type seekoff(off_type off, ios_base::seekdir way,
249
  ios_base::openmode which
250
- = ios_base::in | ios_base::out);
251
  ```
252
 
253
  *Effects:* Alters the stream position within one of the controlled
254
  sequences, if possible, as indicated in
255
  Table  [[tab:iostreams.seekoff.positioning]].
@@ -277,23 +277,24 @@ as indicated in Table  [[tab:iostreams.newoff.values]].
277
  | `way == ios_base::cur` | the next pointer minus the beginning pointer (`xnext - xbeg`). |
278
  | `way == ios_base::end` | the high mark pointer minus the beginning pointer (`high_mark - xbeg`). |
279
 
280
 
281
  If `(newoff + off) < 0`, or if `newoff + off` refers to an uninitialized
282
- character (as defined in  [[stringbuf.members]] paragraph 1), the
283
- positioning operation fails. Otherwise, the function assigns
284
- `xbeg + newoff + off` to the next pointer `xnext`.
285
 
286
  *Returns:* `pos_type(newoff)`, constructed from the resultant offset
287
  `newoff` (of type `off_type`), that stores the resultant stream
288
  position, if possible. If the positioning operation fails, or if the
289
  constructed object cannot represent the resultant stream position, the
290
  return value is `pos_type(off_type(-1))`.
291
 
292
  ``` cpp
293
- pos_type seekpos(pos_type sp, ios_base::openmode which
294
- = ios_base::in | ios_base::out);
 
295
  ```
296
 
297
  *Effects:* Equivalent to `seekoff(off_type(sp), ios_base::beg, which)`.
298
 
299
  *Returns:* `sp` to indicate success, or `pos_type(off_type(-1))` to
 
4
  namespace std {
5
  template <class charT, class traits = char_traits<charT>,
6
  class Allocator = allocator<charT>>
7
  class basic_stringbuf : public basic_streambuf<charT, traits> {
8
  public:
9
+ using char_type = charT;
10
+ using int_type = typename traits::int_type;
11
+ using pos_type = typename traits::pos_type;
12
+ using off_type = typename traits::off_type;
13
+ using traits_type = traits;
14
+ using allocator_type = Allocator;
15
 
16
+ // [stringbuf.cons], constructors
17
+ explicit basic_stringbuf(
18
+ ios_base::openmode which = ios_base::in | ios_base::out);
19
+ explicit basic_stringbuf(
20
+ const basic_string<charT, traits, Allocator>& str,
21
  ios_base::openmode which = ios_base::in | ios_base::out);
22
  basic_stringbuf(const basic_stringbuf& rhs) = delete;
23
  basic_stringbuf(basic_stringbuf&& rhs);
24
 
25
+ // [stringbuf.assign], assign and swap
26
  basic_stringbuf& operator=(const basic_stringbuf& rhs) = delete;
27
  basic_stringbuf& operator=(basic_stringbuf&& rhs);
28
  void swap(basic_stringbuf& rhs);
29
 
30
+ // [stringbuf.members], get and set
31
  basic_string<charT, traits, Allocator> str() const;
32
  void str(const basic_string<charT, traits, Allocator>& s);
33
 
34
  protected:
35
+ // [stringbuf.virtuals], overridden virtual functions
36
+ int_type underflow() override;
37
+ int_type pbackfail(int_type c = traits::eof()) override;
38
+ int_type overflow (int_type c = traits::eof()) override;
39
+ basic_streambuf<charT, traits>* setbuf(charT*, streamsize) override;
40
 
41
+ pos_type seekoff(off_type off, ios_base::seekdir way,
 
42
  ios_base::openmode which
43
+ = ios_base::in | ios_base::out) override;
44
+ pos_type seekpos(pos_type sp,
45
  ios_base::openmode which
46
+ = ios_base::in | ios_base::out) override;
47
 
48
  private:
49
  ios_base::openmode mode; // exposition only
50
  };
51
 
 
67
  read, and `out` set if the output sequence can be written.
68
 
69
  #### `basic_stringbuf` constructors <a id="stringbuf.cons">[[stringbuf.cons]]</a>
70
 
71
  ``` cpp
72
+ explicit basic_stringbuf(
73
+ ios_base::openmode which = ios_base::in | ios_base::out);
74
  ```
75
 
76
  *Effects:* Constructs an object of class `basic_stringbuf`, initializing
77
  the base class with `basic_streambuf()` ([[streambuf.cons]]), and
78
  initializing `mode` with `which`.
79
 
80
+ *Postconditions:* `str() == ""`.
81
 
82
  ``` cpp
83
+ explicit basic_stringbuf(
84
+ const basic_string<charT, traits, Allocator>& s,
85
  ios_base::openmode which = ios_base::in | ios_base::out);
86
  ```
87
 
88
  *Effects:* Constructs an object of class `basic_stringbuf`, initializing
89
  the base class with `basic_streambuf()` ([[streambuf.cons]]), and
 
138
  template <class charT, class traits, class Allocator>
139
  void swap(basic_stringbuf<charT, traits, Allocator>& x,
140
  basic_stringbuf<charT, traits, Allocator>& y);
141
  ```
142
 
143
+ *Effects:* As if by `x.swap(y)`.
144
 
145
  #### Member functions <a id="stringbuf.members">[[stringbuf.members]]</a>
146
 
147
  ``` cpp
148
  basic_string<charT, traits, Allocator> str() const;
 
151
  *Returns:* A `basic_string` object whose content is equal to the
152
  `basic_stringbuf` underlying character sequence. If the
153
  `basic_stringbuf` was created only in input mode, the resultant
154
  `basic_string` contains the character sequence in the range \[`eback()`,
155
  `egptr()`). If the `basic_stringbuf` was created with
156
+ `which & ios_base::out` being nonzero then the resultant `basic_string`
157
  contains the character sequence in the range \[`pbase()`, `high_mark`),
158
  where `high_mark` represents the position one past the highest
159
  initialized character in the buffer. Characters can be initialized by
160
  writing to the stream, by constructing the `basic_stringbuf` with a
161
  `basic_string`, or by calling the `str(basic_string)` member function.
 
172
 
173
  *Effects:* Copies the content of `s` into the `basic_stringbuf`
174
  underlying character sequence and initializes the input and output
175
  sequences according to `mode`.
176
 
177
+ *Postconditions:* If `mode & ios_base::out` is nonzero, `pbase()` points
178
+ to the first underlying character and `epptr()` `>= pbase() + s.size()`
179
+ holds; in addition, if `mode & ios_base::ate` is nonzero,
180
  `pptr() == pbase() + s.size()` holds, otherwise `pptr() == pbase()` is
181
+ `true`. If `mode & ios_base::in` is nonzero, `eback()` points to the
182
+ first underlying character, and both `gptr() == eback()` and
183
  `egptr() == eback() + s.size()` hold.
184
 
185
  #### Overridden virtual functions <a id="stringbuf.virtuals">[[stringbuf.virtuals]]</a>
186
 
187
  ``` cpp
188
+ int_type underflow() override;
189
  ```
190
 
191
  *Returns:* If the input sequence has a read position available, returns
192
  `traits::to_int_type(*gptr())`. Otherwise, returns `traits::eof()`. Any
193
  character in the underlying buffer which has been initialized is
194
  considered to be part of the input sequence.
195
 
196
  ``` cpp
197
+ int_type pbackfail(int_type c = traits::eof()) override;
198
  ```
199
 
200
  *Effects:* Puts back the character designated by `c` to the input
201
  sequence, if possible, in one of three ways:
202
 
 
215
 
216
  *Remarks:* If the function can succeed in more than one of these ways,
217
  it is unspecified which way is chosen.
218
 
219
  ``` cpp
220
+ int_type overflow(int_type c = traits::eof()) override;
221
  ```
222
 
223
  *Effects:* Appends the character designated by `c` to the output
224
  sequence, if possible, in one of two ways:
225
 
 
245
  `egptr()` to point just past the new write position.
246
 
247
  ``` cpp
248
  pos_type seekoff(off_type off, ios_base::seekdir way,
249
  ios_base::openmode which
250
+ = ios_base::in | ios_base::out) override;
251
  ```
252
 
253
  *Effects:* Alters the stream position within one of the controlled
254
  sequences, if possible, as indicated in
255
  Table  [[tab:iostreams.seekoff.positioning]].
 
277
  | `way == ios_base::cur` | the next pointer minus the beginning pointer (`xnext - xbeg`). |
278
  | `way == ios_base::end` | the high mark pointer minus the beginning pointer (`high_mark - xbeg`). |
279
 
280
 
281
  If `(newoff + off) < 0`, or if `newoff + off` refers to an uninitialized
282
+ character ([[stringbuf.members]]), the positioning operation fails.
283
+ Otherwise, the function assigns `xbeg + newoff + off` to the next
284
+ pointer `xnext`.
285
 
286
  *Returns:* `pos_type(newoff)`, constructed from the resultant offset
287
  `newoff` (of type `off_type`), that stores the resultant stream
288
  position, if possible. If the positioning operation fails, or if the
289
  constructed object cannot represent the resultant stream position, the
290
  return value is `pos_type(off_type(-1))`.
291
 
292
  ``` cpp
293
+ pos_type seekpos(pos_type sp,
294
+ ios_base::openmode which
295
+ = ios_base::in | ios_base::out) override;
296
  ```
297
 
298
  *Effects:* Equivalent to `seekoff(off_type(sp), ios_base::beg, which)`.
299
 
300
  *Returns:* `sp` to indicate success, or `pos_type(off_type(-1))` to