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[diff.cpp20.utilities]

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  1. tmp/tmpvsa_72m6/{from.md → to.md} +16 -4
tmp/tmpvsa_72m6/{from.md → to.md} RENAMED
@@ -4,44 +4,56 @@
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  `format_to_n`, `formatted_size`. Removal of `format_args_t`.
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  **Rationale:** Improve safety via compile-time format string checks,
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  avoid unnecessary template instantiations. **Effect on original
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  feature:** Valid C++20 code that contained errors in format strings or
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  relied on previous format string signatures or `format_args_t` may
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- become ill-formed. For example:
 
 
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  ``` cpp
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  auto s = std::format("{:d}", "I am not a number"); // ill-formed,
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  // previously threw format_error
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  ```
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  **Change:** Signature changes: `format`, `format_to`, `format_to_n`,
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  `formatted_size`. **Rationale:** Enable formatting of views that do not
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  support iteration when const-qualified and that are not copyable.
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- **Effect on original feature:** Valid C++20 code that passes bit fields
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- to formatting functions may become ill-formed. For example:
 
 
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  ``` cpp
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  struct tiny {
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  int bit: 1;
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  };
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  auto t = tiny();
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  std::format("{}", t.bit); // ill-formed, previously returned "0"
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  ```
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  **Change:** Restrict types of formatting arguments used as *width* or
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  *precision* in a *std-format-spec*. **Rationale:** Disallow types that
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  do not have useful or portable semantics as a formatting width or
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  precision. **Effect on original feature:** Valid C++20 code that passes
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- a boolean or character type as *arg-id* becomes invalid. For example:
 
 
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  ``` cpp
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  std::format("{:*^{}}", "", true); // ill-formed, previously returned "*"
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  std::format("{:*^{}}", "", '1'); // ill-formed, previously returned an
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  // implementation-defined number of '*' characters
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  ```
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  **Change:** Removed the `formatter` specialization:
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  ``` cpp
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  template<size_t N> struct formatter<const charT[N], charT>;
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  ```
 
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  `format_to_n`, `formatted_size`. Removal of `format_args_t`.
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  **Rationale:** Improve safety via compile-time format string checks,
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  avoid unnecessary template instantiations. **Effect on original
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  feature:** Valid C++20 code that contained errors in format strings or
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  relied on previous format string signatures or `format_args_t` may
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+ become ill-formed.
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+
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+ [*Example 1*:
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  ``` cpp
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  auto s = std::format("{:d}", "I am not a number"); // ill-formed,
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  // previously threw format_error
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  ```
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+ — *end example*]
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+
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  **Change:** Signature changes: `format`, `format_to`, `format_to_n`,
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  `formatted_size`. **Rationale:** Enable formatting of views that do not
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  support iteration when const-qualified and that are not copyable.
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+ **Effect on original feature:** Valid C++20 code that passes bit-fields
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+ to formatting functions may become ill-formed.
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+
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+ [*Example 2*:
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  ``` cpp
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  struct tiny {
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  int bit: 1;
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  };
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  auto t = tiny();
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  std::format("{}", t.bit); // ill-formed, previously returned "0"
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  ```
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+ — *end example*]
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+
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  **Change:** Restrict types of formatting arguments used as *width* or
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  *precision* in a *std-format-spec*. **Rationale:** Disallow types that
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  do not have useful or portable semantics as a formatting width or
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  precision. **Effect on original feature:** Valid C++20 code that passes
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+ a boolean or character type as *arg-id* becomes invalid.
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+
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+ [*Example 3*:
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  ``` cpp
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  std::format("{:*^{}}", "", true); // ill-formed, previously returned "*"
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  std::format("{:*^{}}", "", '1'); // ill-formed, previously returned an
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  // implementation-defined number of '*' characters
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  ```
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+ — *end example*]
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+
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  **Change:** Removed the `formatter` specialization:
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  ``` cpp
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  template<size_t N> struct formatter<const charT[N], charT>;
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  ```