From Jason Turner

[istream.formatted]

C++17 → C++20 5.7 KB 60 lines
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Archived: C++17 | C++20
Markdown: C++17 | C++20
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  1. tmp/tmpp7o7pe99/{from.md → to.md} +25 -28
tmp/tmpp7o7pe99/{from.md → to.md} RENAMED
@@ -4,13 +4,13 @@
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  Each formatted input function begins execution by constructing an object
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  of class `sentry` with the `noskipws` (second) argument `false`. If the
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  `sentry` object returns `true`, when converted to a value of type
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  `bool`, the function endeavors to obtain the requested input. If an
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- exception is thrown during input then `ios::badbit` is turned on[^20] in
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- `*this`’s error state. If `(exceptions()&badbit) != 0` then the
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- exception is rethrown. In any case, the formatted input function
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  destroys the `sentry` object. If no exception has been thrown, it
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  returns `*this`.
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  ##### Arithmetic extractors <a id="istream.formatted.arithmetic">[[istream.formatted.arithmetic]]</a>
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@@ -27,11 +27,11 @@ operator>>(long double& val);
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  operator>>(bool& val);
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  operator>>(void*& val);
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  ```
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  As in the case of the inserters, these extractors depend on the locale’s
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- `num_get<>` ([[locale.num.get]]) object to perform parsing the input
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  stream data. These extractors behave as formatted input functions (as
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  described in  [[istream.formatted.reqmts]]). After a sentry object is
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  constructed, the conversion occurs as if performed by the following code
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  fragment:
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@@ -131,26 +131,23 @@ formatted input function (as described
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  in  [[istream.formatted.reqmts]]).
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  *Returns:* `*this`.
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  ``` cpp
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- template<class charT, class traits>
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- basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& in, charT* s);
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- template<class traits>
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- basic_istream<char, traits>& operator>>(basic_istream<char, traits>& in, unsigned char* s);
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- template<class traits>
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- basic_istream<char, traits>& operator>>(basic_istream<char, traits>& in, signed char* s);
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  ```
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  *Effects:* Behaves like a formatted input member (as described
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  in  [[istream.formatted.reqmts]]) of `in`. After a `sentry` object is
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- constructed, `operator>>` extracts characters and stores them into
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- successive locations of an array whose first element is designated by
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- `s`. If `width()` is greater than zero, `n` is `width()`. Otherwise `n`
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- is the number of elements of the largest array of `char_type` that can
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- store a terminating `charT()`. `n` is the maximum number of characters
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- stored.
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  Characters are extracted and stored until any of the following occurs:
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  - `n-1` characters are stored;
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  - end of file occurs on the input sequence;
@@ -160,11 +157,11 @@ Characters are extracted and stored until any of the following occurs:
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  `operator>>` then stores a null byte (`charT()`) in the next position,
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  which may be the first position if no characters were extracted.
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  `operator>>` then calls `width(0)`.
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  If the function extracted no characters, it calls `setstate(failbit)`,
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- which may throw `ios_base::failure` ([[iostate.flags]]).
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  *Returns:* `in`.
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  ``` cpp
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  template<class charT, class traits>
@@ -184,26 +181,26 @@ stored in `c`. Otherwise, the function calls `in.setstate(failbit)`.
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  ``` cpp
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  basic_istream<charT, traits>& operator>>(basic_streambuf<charT, traits>* sb);
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  ```
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- *Effects:* Behaves as an unformatted input function
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- ([[istream.unformatted]]). If `sb` is null, calls `setstate(failbit)`,
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- which may throw `ios_base::failure` ([[iostate.flags]]). After a sentry
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- object is constructed, extracts characters from `*this` and inserts them
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- in the output sequence controlled by `sb`. Characters are extracted and
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- inserted until any of the following occurs:
 
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  - end-of-file occurs on the input sequence;
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  - inserting in the output sequence fails (in which case the character to
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  be inserted is not extracted);
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  - an exception occurs (in which case the exception is caught).
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  If the function inserts no characters, it calls `setstate(failbit)`,
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- which may throw `ios_base::failure` ([[iostate.flags]]). If it inserted
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- no characters because it caught an exception thrown while extracting
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- characters from `*this` and `failbit` is on in
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- `exceptions()` ([[iostate.flags]]), then the caught exception is
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- rethrown.
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  *Returns:* `*this`.
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  Each formatted input function begins execution by constructing an object
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  of class `sentry` with the `noskipws` (second) argument `false`. If the
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  `sentry` object returns `true`, when converted to a value of type
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  `bool`, the function endeavors to obtain the requested input. If an
9
+ exception is thrown during input then `ios_base::badbit` is turned
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+ on[^20] in `*this`’s error state. If `(exceptions()&badbit) != 0` then
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+ the exception is rethrown. In any case, the formatted input function
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  destroys the `sentry` object. If no exception has been thrown, it
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  returns `*this`.
14
 
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  ##### Arithmetic extractors <a id="istream.formatted.arithmetic">[[istream.formatted.arithmetic]]</a>
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  operator>>(bool& val);
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  operator>>(void*& val);
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  ```
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  As in the case of the inserters, these extractors depend on the locale’s
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+ `num_get<>` [[locale.num.get]] object to perform parsing the input
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  stream data. These extractors behave as formatted input functions (as
34
  described in  [[istream.formatted.reqmts]]). After a sentry object is
35
  constructed, the conversion occurs as if performed by the following code
36
  fragment:
37
 
 
131
  in  [[istream.formatted.reqmts]]).
132
 
133
  *Returns:* `*this`.
134
 
135
  ``` cpp
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+ template<class charT, class traits, size_t N>
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+ basic_istream<charT, traits>& operator>>(basic_istream<charT, traits>& in, charT (&s)[N]);
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+ template<class traits, size_t N>
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+ basic_istream<char, traits>& operator>>(basic_istream<char, traits>& in, unsigned char (&s)[N]);
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+ template<class traits, size_t N>
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+ basic_istream<char, traits>& operator>>(basic_istream<char, traits>& in, signed char (&s)[N]);
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  ```
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  *Effects:* Behaves like a formatted input member (as described
145
  in  [[istream.formatted.reqmts]]) of `in`. After a `sentry` object is
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+ constructed, `operator>>` extracts characters and stores them into `s`.
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+ If `width()` is greater than zero, `n` is `min(size_t(width()), N)`.
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+ Otherwise `n` is `N`. `n` is the maximum number of characters stored.
 
 
 
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  Characters are extracted and stored until any of the following occurs:
151
 
152
  - `n-1` characters are stored;
153
  - end of file occurs on the input sequence;
 
157
  `operator>>` then stores a null byte (`charT()`) in the next position,
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  which may be the first position if no characters were extracted.
159
  `operator>>` then calls `width(0)`.
160
 
161
  If the function extracted no characters, it calls `setstate(failbit)`,
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+ which may throw `ios_base::failure` [[iostate.flags]].
163
 
164
  *Returns:* `in`.
165
 
166
  ``` cpp
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  template<class charT, class traits>
 
181
 
182
  ``` cpp
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  basic_istream<charT, traits>& operator>>(basic_streambuf<charT, traits>* sb);
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  ```
185
 
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+ *Effects:* Behaves as an unformatted input
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+ function [[istream.unformatted]]. If `sb` is null, calls
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+ `setstate(failbit)`, which may throw `ios_base::failure`
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+ [[iostate.flags]]. After a sentry object is constructed, extracts
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+ characters from `*this` and inserts them in the output sequence
191
+ controlled by `sb`. Characters are extracted and inserted until any of
192
+ the following occurs:
193
 
194
  - end-of-file occurs on the input sequence;
195
  - inserting in the output sequence fails (in which case the character to
196
  be inserted is not extracted);
197
  - an exception occurs (in which case the exception is caught).
198
 
199
  If the function inserts no characters, it calls `setstate(failbit)`,
200
+ which may throw `ios_base::failure` [[iostate.flags]]. If it inserted no
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+ characters because it caught an exception thrown while extracting
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+ characters from `*this` and `failbit` is set in `exceptions()`
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+ [[iostate.flags]], then the caught exception is rethrown.
 
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  *Returns:* `*this`.
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