From Jason Turner

[ostream.formatted.print]

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  1. tmp/tmpmx_72za3/{from.md → to.md} +27 -16
tmp/tmpmx_72za3/{from.md → to.md} RENAMED
@@ -7,28 +7,38 @@ template<class... Args>
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  *Effects:* If the ordinary literal encoding [[lex.charset]] is UTF-8,
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  equivalent to:
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  ``` cpp
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- vprint_unicode(os, fmt.str, make_format_args(std::forward<Args>(args)...));
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  ```
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  Otherwise, equivalent to:
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  ``` cpp
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- vprint_nonunicode(os, fmt.str, make_format_args(std::forward<Args>(args)...));
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  ```
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  ``` cpp
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  template<class... Args>
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  void println(ostream& os, format_string<Args...> fmt, Args&&... args);
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  ```
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  *Effects:* Equivalent to:
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  ``` cpp
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- print(os, "{}\n", format(fmt, std::forward<Args>(args)...));
 
 
 
 
 
 
 
 
 
 
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  ```
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  ``` cpp
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  void vprint_unicode(ostream& os, string_view fmt, format_args args);
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  void vprint_nonunicode(ostream& os, string_view fmt, format_args args);
@@ -40,28 +50,29 @@ function [[ostream.formatted.reqmts]] of `os`, except that:
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  - failure to generate output is reported as specified below, and
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  - any exception thrown by the call to `vformat` is propagated without
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  regard to the value of `os.exceptions()` and without turning on
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  `ios_base::badbit` in the error state of `os`.
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- After constructing a `sentry` object, the function initializes an
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- automatic variable via
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  ``` cpp
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  string out = vformat(os.getloc(), fmt, args);
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  ```
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- If the function is `vprint_unicode` and `os` is a stream that refers to
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- a terminal capable of displaying Unicode which is determined in an
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- implementation-defined manner, writes `out` to the terminal using the
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- native Unicode API; if `out` contains invalid code units, the behavior
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- is undefined and implementations are encouraged to diagnose it. If the
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- native Unicode API is used, the function flushes `os` before writing
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- `out`. Otherwise (if `os` is not such a stream or the function is
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- `vprint_nonunicode`), inserts the character sequence \[`out.begin()`,
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- `out.end()`) into `os`. If writing to the terminal or inserting into
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- `os` fails, calls `os.setstate(ios_base::badbit)` (which may throw
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- `ios_base::failure`).
 
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  *Recommended practice:* For `vprint_unicode`, if invoking the native
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  Unicode API requires transcoding, implementations should substitute
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  invalid code units with U+fffd (replacement character) per the Unicode
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  Standard, Chapter 3.9 ‘U+fffd‘ Substitution in Conversion.
 
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  *Effects:* If the ordinary literal encoding [[lex.charset]] is UTF-8,
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  equivalent to:
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  ``` cpp
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+ vprint_unicode(os, fmt.str, make_format_args(args...));
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  ```
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  Otherwise, equivalent to:
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  ``` cpp
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+ vprint_nonunicode(os, fmt.str, make_format_args(args...));
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  ```
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  ``` cpp
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  template<class... Args>
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  void println(ostream& os, format_string<Args...> fmt, Args&&... args);
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  ```
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  *Effects:* Equivalent to:
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  ``` cpp
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+ print(os, "{}\n", format(os.getloc(), fmt, std::forward<Args>(args)...));
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+ ```
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+
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+ ``` cpp
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+ void println(ostream& os);
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+ ```
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+
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+ *Effects:* Equivalent to:
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+
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+ ``` cpp
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+ print(os, "\n");
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  ```
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  ``` cpp
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  void vprint_unicode(ostream& os, string_view fmt, format_args args);
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  void vprint_nonunicode(ostream& os, string_view fmt, format_args args);
 
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  - failure to generate output is reported as specified below, and
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  - any exception thrown by the call to `vformat` is propagated without
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  regard to the value of `os.exceptions()` and without turning on
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  `ios_base::badbit` in the error state of `os`.
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+ After constructing a `sentry` object, the function initializes a
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+ variable with automatic storage duration via
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  ``` cpp
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  string out = vformat(os.getloc(), fmt, args);
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  ```
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+ - If the function is `vprint_unicode` and `os` is a stream that refers
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+ to a terminal that is capable of displaying Unicode only via a native
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+ Unicode API, which is determined in an implementation-defined manner,
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+ flushes `os` and then writes `out` to the terminal using the native
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+ Unicode API; if `out` contains invalid code units, the behavior is
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+ undefined. Then establishes an observable
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+ checkpoint [[intro.abstract]].
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+ - Otherwise inserts the character sequence \[`out.begin()`, `out.end()`)
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+ into `os`.
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+
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+ If writing to the terminal or inserting into `os` fails, calls
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+ `os.setstate(ios_base::badbit)` (which may throw `ios_base::failure`).
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  *Recommended practice:* For `vprint_unicode`, if invoking the native
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  Unicode API requires transcoding, implementations should substitute
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  invalid code units with U+fffd (replacement character) per the Unicode
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  Standard, Chapter 3.9 ‘U+fffd‘ Substitution in Conversion.