external: Update fmtlib.

external/fmt/include/fmt/args.h

@@ -1,4 +1,4 @@
-// Formatting library for C++ - dynamic format arguments
+// Formatting library for C++ - dynamic argument lists
 //
 // Copyright (c) 2012 - present, Victor Zverovich
 // All rights reserved.
@@ -8,11 +8,13 @@
 #ifndef FMT_ARGS_H_
 #define FMT_ARGS_H_
 
-#include <functional>  // std::reference_wrapper
-#include <memory>      // std::unique_ptr
-#include <vector>
+#ifndef FMT_MODULE
+#  include <functional>  // std::reference_wrapper
+#  include <memory>      // std::unique_ptr
+#  include <vector>
+#endif
 
-#include "core.h"
+#include "format.h"  // std_string_view
 
 FMT_BEGIN_NAMESPACE
 
@@ -22,20 +24,24 @@ template <typename T> struct is_reference_wrapper : std::false_type {};
 template <typename T>
 struct is_reference_wrapper<std::reference_wrapper<T>> : std::true_type {};
 
-template <typename T> const T& unwrap(const T& v) { return v; }
-template <typename T> const T& unwrap(const std::reference_wrapper<T>& v) {
+template <typename T> auto unwrap(const T& v) -> const T& { return v; }
+template <typename T>
+auto unwrap(const std::reference_wrapper<T>& v) -> const T& {
   return static_cast<const T&>(v);
 }
 
-class dynamic_arg_list {
-  // Workaround for clang's -Wweak-vtables. Unlike for regular classes, for
-  // templates it doesn't complain about inability to deduce single translation
-  // unit for placing vtable. So storage_node_base is made a fake template.
-  template <typename = void> struct node {
-    virtual ~node() = default;
-    std::unique_ptr<node<>> next;
-  };
+// node is defined outside dynamic_arg_list to workaround a C2504 bug in MSVC
+// 2022 (v17.10.0).
+//
+// Workaround for clang's -Wweak-vtables. Unlike for regular classes, for
+// templates it doesn't complain about inability to deduce single translation
+// unit for placing vtable. So node is made a fake template.
+template <typename = void> struct node {
+  virtual ~node() = default;
+  std::unique_ptr<node<>> next;
+};
 
+class dynamic_arg_list {
   template <typename T> struct typed_node : node<> {
     T value;
 
@@ -50,7 +56,7 @@ class dynamic_arg_list {
   std::unique_ptr<node<>> head_;
 
  public:
-  template <typename T, typename Arg> const T& push(const Arg& arg) {
+  template <typename T, typename Arg> auto push(const Arg& arg) -> const T& {
     auto new_node = std::unique_ptr<typed_node<T>>(new typed_node<T>(arg));
     auto& value = new_node->value;
     new_node->next = std::move(head_);
@@ -61,14 +67,10 @@ class dynamic_arg_list {
 }  // namespace detail
 
 /**
-  \rst
-  A dynamic version of `fmt::format_arg_store`.
-  It's equipped with a storage to potentially temporary objects which lifetimes
-  could be shorter than the format arguments object.
-
-  It can be implicitly converted into `~fmt::basic_format_args` for passing
-  into type-erased formatting functions such as `~fmt::vformat`.
-  \endrst
+ * A dynamic list of formatting arguments with storage.
+ *
+ * It can be implicitly converted into `fmt::basic_format_args` for passing
+ * into type-erased formatting functions such as `fmt::vformat`.
  */
 template <typename Context>
 class dynamic_format_arg_store
@@ -110,14 +112,14 @@ class dynamic_format_arg_store
 
   friend class basic_format_args<Context>;
 
-  unsigned long long get_types() const {
+  auto get_types() const -> unsigned long long {
     return detail::is_unpacked_bit | data_.size() |
            (named_info_.empty()
                 ? 0ULL
                 : static_cast<unsigned long long>(detail::has_named_args_bit));
   }
 
-  const basic_format_arg<Context>* data() const {
+  auto data() const -> const basic_format_arg<Context>* {
     return named_info_.empty() ? data_.data() : data_.data() + 1;
   }
 
@@ -146,22 +148,20 @@ class dynamic_format_arg_store
   constexpr dynamic_format_arg_store() = default;
 
   /**
-    \rst
-    Adds an argument into the dynamic store for later passing to a formatting
-    function.
-
-    Note that custom types and string types (but not string views) are copied
-    into the store dynamically allocating memory if necessary.
-
-    **Example**::
-
-      fmt::dynamic_format_arg_store<fmt::format_context> store;
-      store.push_back(42);
-      store.push_back("abc");
-      store.push_back(1.5f);
-      std::string result = fmt::vformat("{} and {} and {}", store);
-    \endrst
-  */
+   * Adds an argument into the dynamic store for later passing to a formatting
+   * function.
+   *
+   * Note that custom types and string types (but not string views) are copied
+   * into the store dynamically allocating memory if necessary.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     store.push_back(42);
+   *     store.push_back("abc");
+   *     store.push_back(1.5f);
+   *     std::string result = fmt::vformat("{} and {} and {}", store);
+   */
   template <typename T> void push_back(const T& arg) {
     if (detail::const_check(need_copy<T>::value))
       emplace_arg(dynamic_args_.push<stored_type<T>>(arg));
@@ -170,20 +170,18 @@ class dynamic_format_arg_store
   }
 
   /**
-    \rst
-    Adds a reference to the argument into the dynamic store for later passing to
-    a formatting function.
-
-    **Example**::
-
-      fmt::dynamic_format_arg_store<fmt::format_context> store;
-      char band[] = "Rolling Stones";
-      store.push_back(std::cref(band));
-      band[9] = 'c'; // Changing str affects the output.
-      std::string result = fmt::vformat("{}", store);
-      // result == "Rolling Scones"
-    \endrst
-  */
+   * Adds a reference to the argument into the dynamic store for later passing
+   * to a formatting function.
+   *
+   * **Example**:
+   *
+   *     fmt::dynamic_format_arg_store<fmt::format_context> store;
+   *     char band[] = "Rolling Stones";
+   *     store.push_back(std::cref(band));
+   *     band[9] = 'c'; // Changing str affects the output.
+   *     std::string result = fmt::vformat("{}", store);
+   *     // result == "Rolling Scones"
+   */
   template <typename T> void push_back(std::reference_wrapper<T> arg) {
     static_assert(
         need_copy<T>::value,
@@ -192,10 +190,10 @@ class dynamic_format_arg_store
   }
 
   /**
-    Adds named argument into the dynamic store for later passing to a formatting
-    function. ``std::reference_wrapper`` is supported to avoid copying of the
-    argument. The name is always copied into the store.
-  */
+   * Adds named argument into the dynamic store for later passing to a
+   * formatting function. `std::reference_wrapper` is supported to avoid
+   * copying of the argument. The name is always copied into the store.
+   */
   template <typename T>
   void push_back(const detail::named_arg<char_type, T>& arg) {
     const char_type* arg_name =
@@ -208,19 +206,15 @@ class dynamic_format_arg_store
     }
   }
 
-  /** Erase all elements from the store */
+  /// Erase all elements from the store.
   void clear() {
     data_.clear();
     named_info_.clear();
     dynamic_args_ = detail::dynamic_arg_list();
   }
 
-  /**
-    \rst
-    Reserves space to store at least *new_cap* arguments including
-    *new_cap_named* named arguments.
-    \endrst
-  */
+  /// Reserves space to store at least `new_cap` arguments including
+  /// `new_cap_named` named arguments.
   void reserve(size_t new_cap, size_t new_cap_named) {
     FMT_ASSERT(new_cap >= new_cap_named,
                "Set of arguments includes set of named arguments");