From Jason Turner

[locale.time.get]

C++14 → C++17 8.5 KB 73 lines
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Archived: C++14 | C++17
Markdown: C++14 | C++17
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  1. tmp/tmptvpup3h6/{from.md → to.md} +34 -33
tmp/tmptvpup3h6/{from.md → to.md} RENAMED
@@ -8,12 +8,12 @@ namespace std {
8
  };
9
 
10
  template <class charT, class InputIterator = istreambuf_iterator<charT>>
11
  class time_get : public locale::facet, public time_base {
12
  public:
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- typedef charT char_type;
14
- typedef InputIterator iter_type;
15
 
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  explicit time_get(size_t refs = 0);
17
 
18
  dateorder date_order() const { return do_date_order(); }
19
  iter_type get_time(iter_type s, iter_type end, ios_base& f,
@@ -54,81 +54,81 @@ namespace std {
54
  ```
55
 
56
  `time_get`
57
 
58
  is used to parse a character sequence, extracting components of a time
59
- or date into a `struct tm` record. Each `get` member parses a format as
60
  produced by a corresponding format specifier to `time_put<>::put`. If
61
  the sequence being parsed matches the correct format, the corresponding
62
  members of the `struct tm` argument are set to the values used to
63
  produce the sequence; otherwise either an error is reported or
64
- unspecified values are assigned.[^14]
65
 
66
  If the end iterator is reached during parsing by any of the `get()`
67
  member functions, the member sets `ios_base::eofbit` in `err`.
68
 
69
  ##### `time_get` members <a id="locale.time.get.members">[[locale.time.get.members]]</a>
70
 
71
  ``` cpp
72
  dateorder date_order() const;
73
  ```
74
 
75
- *Returns:* `do_date_order()`
76
 
77
  ``` cpp
78
  iter_type get_time(iter_type s, iter_type end, ios_base& str,
79
  ios_base::iostate& err, tm* t) const;
80
  ```
81
 
82
- *Returns:* `do_get_time(s, end, str, err, t)`
83
 
84
  ``` cpp
85
  iter_type get_date(iter_type s, iter_type end, ios_base& str,
86
  ios_base::iostate& err, tm* t) const;
87
  ```
88
 
89
- *Returns:* `do_get_date(s, end, str, err, t)`
90
 
91
  ``` cpp
92
  iter_type get_weekday(iter_type s, iter_type end, ios_base& str,
93
  ios_base::iostate& err, tm* t) const;
94
  iter_type get_monthname(iter_type s, iter_type end, ios_base& str,
95
  ios_base::iostate& err, tm* t) const;
96
  ```
97
 
98
  *Returns:* `do_get_weekday(s, end, str, err, t)` or
99
- `do_get_monthname(s, end, str, err, t)`
100
 
101
  ``` cpp
102
  iter_type get_year(iter_type s, iter_type end, ios_base& str,
103
  ios_base::iostate& err, tm* t) const;
104
  ```
105
 
106
- *Returns:* `do_get_year(s, end, str, err, t)`
107
 
108
  ``` cpp
109
- iter_type get(iter_type s, iter_type end, ios_base& f,
110
- ios_base::iostate& err, tm* t, char format, char modifier = 0) const;
111
  ```
112
 
113
- *Returns:* `do_get(s, end, f, err, t, format, modifier)`
114
 
115
  ``` cpp
116
- iter_type get(iter_type s, iter_type end, ios_base& f,
117
- ios_base::iostate& err, tm* t, const char_type* fmt, const char_type* fmtend) const;
118
  ```
119
 
120
  *Requires:* \[`fmt`, `fmtend`) shall be a valid range.
121
 
122
  *Effects:* The function starts by evaluating `err = ios_base::goodbit`.
123
  It then enters a loop, reading zero or more characters from `s` at each
124
  iteration. Unless otherwise specified below, the loop terminates when
125
  the first of the following conditions holds:
126
 
127
- - The expression `fmt == fmtend` evaluates to true.
128
- - The expression `err == ios_base::goodbit` evaluates to false.
129
- - The expression `s == end` evaluates to true, in which case the
130
  function evaluates `err = ios_base::eofbit | ios_base::failbit`.
131
  - The next element of `fmt` is equal to `’%’`, optionally followed by a
132
  modifier character, followed by a conversion specifier character,
133
  `format`, together forming a conversion specification valid for the
134
  ISO/IEC 9945 function `strptime`. If the number of elements in the
@@ -139,36 +139,37 @@ the first of the following conditions holds:
139
  value of `modifier` is `’\0’` when the optional modifier is absent
140
  from the conversion specification. If `err == ios_base::goodbit` holds
141
  after the evaluation of the expression, the function increments `fmt`
142
  to point just past the end of the conversion specification and
143
  continues looping.
144
- - The expression `isspace(*fmt, f.getloc())` evaluates to true, in which
145
- case the function first increments `fmt` until
146
- `fmt == fmtend || !isspace(*fmt, f.getloc())` evaluates to true, then
147
- advances `s` until `s == end || !isspace(*s, f.getloc())` is true, and
148
- finally resumes looping.
149
  - The next character read from `s` matches the element pointed to by
150
  `fmt` in a case-insensitive comparison, in which case the function
151
  evaluates `++fmt, ++s` and continues looping. Otherwise, the function
152
  evaluates `err = ios_base::failbit`.
153
 
154
- The function uses the `ctype<charT>` facet installed in `f`’s locale to
155
- determine valid whitespace characters. It is unspecified by what means
156
- the function performs case-insensitive comparison or whether
157
- multi-character sequences are considered while doing so.
 
158
 
159
- *Returns:* `s`
160
 
161
  ##### `time_get` virtual functions <a id="locale.time.get.virtuals">[[locale.time.get.virtuals]]</a>
162
 
163
  ``` cpp
164
  dateorder do_date_order() const;
165
  ```
166
 
167
  *Returns:* An enumeration value indicating the preferred order of
168
  components for those date formats that are composed of day, month, and
169
- year.[^15] Returns `no_order` if the date format specified by `’x’`
170
  contains other variable components (e.g., Julian day, week number, week
171
  day).
172
 
173
  ``` cpp
174
  iter_type do_get_time(iter_type s, iter_type end, ios_base& str,
@@ -255,24 +256,24 @@ any remaining format characters, corresponding to a conversion directive
255
  appropriate for the ISO/IEC 9945 function `strptime`, formed by
256
  concatenating `’%’`, the `modifier` character, when non-NUL, and the
257
  `format` character. When the concatenation fails to yield a complete
258
  valid directive the function leaves the object pointed to by `t`
259
  unchanged and evaluates `err |= ios_base::failbit`. When `s == end`
260
- evaluates to true after reading a character the function evaluates
261
  `err |= ios_base::eofbit`.
262
 
263
  For complex conversion directives such as `%c`, `%x`, or `%X`, or
264
  directives that involve the optional modifiers `E` or `O`, when the
265
  function is unable to unambiguously determine some or all `struct tm`
266
  members from the input sequence \[`s`, `end`), it evaluates
267
  `err |= ios_base::eofbit`. In such cases the values of those `struct tm`
268
  members are unspecified and may be outside their valid range.
269
 
270
- It is unspecified whether multiple calls to `do_get()` with the address
271
- of the same `struct tm` object will update the current contents of the
272
- object or simply overwrite its members. Portable programs must zero out
273
- the object before invoking the function.
274
 
275
  *Returns:* An iterator pointing immediately beyond the last character
276
  recognized as possibly part of a valid input sequence for the given
277
  `format` and `modifier`.
278
 
 
8
  };
9
 
10
  template <class charT, class InputIterator = istreambuf_iterator<charT>>
11
  class time_get : public locale::facet, public time_base {
12
  public:
13
+ using char_type = charT;
14
+ using iter_type = InputIterator;
15
 
16
  explicit time_get(size_t refs = 0);
17
 
18
  dateorder date_order() const { return do_date_order(); }
19
  iter_type get_time(iter_type s, iter_type end, ios_base& f,
 
54
  ```
55
 
56
  `time_get`
57
 
58
  is used to parse a character sequence, extracting components of a time
59
+ or date into a `struct tm` object. Each `get` member parses a format as
60
  produced by a corresponding format specifier to `time_put<>::put`. If
61
  the sequence being parsed matches the correct format, the corresponding
62
  members of the `struct tm` argument are set to the values used to
63
  produce the sequence; otherwise either an error is reported or
64
+ unspecified values are assigned.[^15]
65
 
66
  If the end iterator is reached during parsing by any of the `get()`
67
  member functions, the member sets `ios_base::eofbit` in `err`.
68
 
69
  ##### `time_get` members <a id="locale.time.get.members">[[locale.time.get.members]]</a>
70
 
71
  ``` cpp
72
  dateorder date_order() const;
73
  ```
74
 
75
+ *Returns:* `do_date_order()`.
76
 
77
  ``` cpp
78
  iter_type get_time(iter_type s, iter_type end, ios_base& str,
79
  ios_base::iostate& err, tm* t) const;
80
  ```
81
 
82
+ *Returns:* `do_get_time(s, end, str, err, t)`.
83
 
84
  ``` cpp
85
  iter_type get_date(iter_type s, iter_type end, ios_base& str,
86
  ios_base::iostate& err, tm* t) const;
87
  ```
88
 
89
+ *Returns:* `do_get_date(s, end, str, err, t)`.
90
 
91
  ``` cpp
92
  iter_type get_weekday(iter_type s, iter_type end, ios_base& str,
93
  ios_base::iostate& err, tm* t) const;
94
  iter_type get_monthname(iter_type s, iter_type end, ios_base& str,
95
  ios_base::iostate& err, tm* t) const;
96
  ```
97
 
98
  *Returns:* `do_get_weekday(s, end, str, err, t)` or
99
+ `do_get_monthname(s, end, str, err, t)`.
100
 
101
  ``` cpp
102
  iter_type get_year(iter_type s, iter_type end, ios_base& str,
103
  ios_base::iostate& err, tm* t) const;
104
  ```
105
 
106
+ *Returns:* `do_get_year(s, end, str, err, t)`.
107
 
108
  ``` cpp
109
+ iter_type get(iter_type s, iter_type end, ios_base& f, ios_base::iostate& err,
110
+ tm* t, char format, char modifier = 0) const;
111
  ```
112
 
113
+ *Returns:* `do_get(s, end, f, err, t, format, modifier)`.
114
 
115
  ``` cpp
116
+ iter_type get(iter_type s, iter_type end, ios_base& f, ios_base::iostate& err,
117
+ tm* t, const char_type* fmt, const char_type* fmtend) const;
118
  ```
119
 
120
  *Requires:* \[`fmt`, `fmtend`) shall be a valid range.
121
 
122
  *Effects:* The function starts by evaluating `err = ios_base::goodbit`.
123
  It then enters a loop, reading zero or more characters from `s` at each
124
  iteration. Unless otherwise specified below, the loop terminates when
125
  the first of the following conditions holds:
126
 
127
+ - The expression `fmt == fmtend` evaluates to `true`.
128
+ - The expression `err == ios_base::goodbit` evaluates to `false`.
129
+ - The expression `s == end` evaluates to `true`, in which case the
130
  function evaluates `err = ios_base::eofbit | ios_base::failbit`.
131
  - The next element of `fmt` is equal to `’%’`, optionally followed by a
132
  modifier character, followed by a conversion specifier character,
133
  `format`, together forming a conversion specification valid for the
134
  ISO/IEC 9945 function `strptime`. If the number of elements in the
 
139
  value of `modifier` is `’\0’` when the optional modifier is absent
140
  from the conversion specification. If `err == ios_base::goodbit` holds
141
  after the evaluation of the expression, the function increments `fmt`
142
  to point just past the end of the conversion specification and
143
  continues looping.
144
+ - The expression `isspace(*fmt, f.getloc())` evaluates to `true`, in
145
+ which case the function first increments `fmt` until
146
+ `fmt == fmtend || !isspace(*fmt, f.getloc())` evaluates to `true`,
147
+ then advances `s` until `s == end || !isspace(*s, f.getloc())` is
148
+ `true`, and finally resumes looping.
149
  - The next character read from `s` matches the element pointed to by
150
  `fmt` in a case-insensitive comparison, in which case the function
151
  evaluates `++fmt, ++s` and continues looping. Otherwise, the function
152
  evaluates `err = ios_base::failbit`.
153
 
154
+ [*Note 1*: The function uses the `ctype<charT>` facet installed in
155
+ `f`’s locale to determine valid whitespace characters. It is unspecified
156
+ by what means the function performs case-insensitive comparison or
157
+ whether multi-character sequences are considered while doing
158
+ so. — *end note*]
159
 
160
+ *Returns:* `s`.
161
 
162
  ##### `time_get` virtual functions <a id="locale.time.get.virtuals">[[locale.time.get.virtuals]]</a>
163
 
164
  ``` cpp
165
  dateorder do_date_order() const;
166
  ```
167
 
168
  *Returns:* An enumeration value indicating the preferred order of
169
  components for those date formats that are composed of day, month, and
170
+ year.[^16] Returns `no_order` if the date format specified by `’x’`
171
  contains other variable components (e.g., Julian day, week number, week
172
  day).
173
 
174
  ``` cpp
175
  iter_type do_get_time(iter_type s, iter_type end, ios_base& str,
 
256
  appropriate for the ISO/IEC 9945 function `strptime`, formed by
257
  concatenating `’%’`, the `modifier` character, when non-NUL, and the
258
  `format` character. When the concatenation fails to yield a complete
259
  valid directive the function leaves the object pointed to by `t`
260
  unchanged and evaluates `err |= ios_base::failbit`. When `s == end`
261
+ evaluates to `true` after reading a character the function evaluates
262
  `err |= ios_base::eofbit`.
263
 
264
  For complex conversion directives such as `%c`, `%x`, or `%X`, or
265
  directives that involve the optional modifiers `E` or `O`, when the
266
  function is unable to unambiguously determine some or all `struct tm`
267
  members from the input sequence \[`s`, `end`), it evaluates
268
  `err |= ios_base::eofbit`. In such cases the values of those `struct tm`
269
  members are unspecified and may be outside their valid range.
270
 
271
+ *Remarks:* It is unspecified whether multiple calls to `do_get()` with
272
+ the address of the same `struct tm` object will update the current
273
+ contents of the object or simply overwrite its members. Portable
274
+ programs must zero out the object before invoking the function.
275
 
276
  *Returns:* An iterator pointing immediately beyond the last character
277
  recognized as possibly part of a valid input sequence for the given
278
  `format` and `modifier`.
279