Make format a non-member

include/fmt/compile.h

@@ -206,15 +206,6 @@ class prepared_format {
     return {it.base(), it.count()};
   }
 
-  std::basic_string<char_type> format(const Args&... args) const {
-    basic_memory_buffer<char_type> buffer;
-    using range = buffer_range<char_type>;
-    this->vformat_to(range(buffer),
-                     basic_format_args<context>{
-                         make_args_checked<Args...>(format_, args...)});
-    return to_string(buffer);
-  }
-
   template <typename Container, FMT_ENABLE_IF(is_contiguous<Container>::value)>
   inline std::back_insert_iterator<Container> format_to(
       std::back_insert_iterator<Container> out, Args&&... args) const {
@@ -243,7 +234,6 @@ class prepared_format {
                                 make_args_checked<Args...>(format_, args...)});
   }
 
- private:
   typedef buffer_context<char_type> context;
 
   template <typename Range, typename Context>
@@ -304,6 +294,7 @@ class prepared_format {
     return ctx.out();
   }
 
+ private:
   void advance_parse_context_to_specification(
       basic_parse_context<char_type>& parse_ctx,
       const format_part_t& part) const {
@@ -677,9 +668,10 @@ auto do_compile(const Format& format)
 }
 #endif
 
-template <typename... Args> using prepared_format_t =
-  typename basic_prepared_format<
-      std::string, parts_container<char>, Args...>::type;
+template <typename... Args>
+using prepared_format_t =
+    typename basic_prepared_format<std::string, parts_container<char>,
+                                   Args...>::type;
 }  // namespace internal
 
 #if FMT_USE_CONSTEXPR
@@ -720,6 +712,17 @@ auto compile(basic_string_view<Char> format_str) ->
   return compile<Args...>(internal::to_runtime_format(format_str));
 }
 
+template <typename CompiledFormat, typename... Args,
+          typename Char = typename CompiledFormat::char_type>
+std::basic_string<Char> format(const CompiledFormat& cf, const Args&... args) {
+  basic_memory_buffer<Char> buffer;
+  using range = internal::buffer_range<Char>;
+  using context = buffer_context<Char>;
+  cf.template vformat_to<range, context>(range(buffer),
+                                         {make_format_args<context>(args...)});
+  return to_string(buffer);
+}
+
 FMT_END_NAMESPACE
 
 #endif  // FMT_COMPILE_H_

test/compile-test.cc

@@ -449,11 +449,11 @@ template <typename... Args> struct copied_prepared_format_creator {
 TEST(PrepareTest, CopyPreparedFormat_InternalStringViewsAreNotInvalidated) {
   auto prepared = copied_prepared_format_creator<int, std::string>::make(
       "before {} middle {} after");
-  EXPECT_EQ("before 42 middle text after", prepared.format(42, "text"));
+  EXPECT_EQ("before 42 middle text after", fmt::format(prepared, 42, "text"));
 
   prepared = copied_prepared_format_creator<int, std::string>::make(
       "before {0} middle {1} after");
-  EXPECT_EQ("before 42 middle text after", prepared.format(42, "text"));
+  EXPECT_EQ("before 42 middle text after", fmt::format(prepared, 42, "text"));
 
   {
     typedef decltype(fmt::arg("first", 42)) argument0;
@@ -462,7 +462,7 @@ TEST(PrepareTest, CopyPreparedFormat_InternalStringViewsAreNotInvalidated) {
         copied_prepared_format_creator<argument0, argument1>::make(
             "before {first} middle {second} after");
     EXPECT_EQ("before 42 middle text after",
-              named_prepared.format(fmt::arg("first", 42),
+              fmt::format(named_prepared, fmt::arg("first", 42),
                                     fmt::arg("second", "text")));
   }
   {
@@ -472,7 +472,7 @@ TEST(PrepareTest, CopyPreparedFormat_InternalStringViewsAreNotInvalidated) {
         copied_prepared_format_creator<argument0, argument1>::make(
             ">>>{value:>{width}}<<<");
     EXPECT_EQ(">>>     12345<<<",
-              named_prepared.format(fmt::arg("value", "12345"),
+              fmt::format(named_prepared, fmt::arg("value", "12345"),
                                     fmt::arg("width", 10)));
   }
 }
@@ -481,9 +481,9 @@ TEST(PrepareTest, ReusedPreparedFormatType) {
   using prepared_format = fmt::internal::prepared_format_t<std::string, int>;
 
   prepared_format prepared = fmt::compile<prepared_format>("The {} is {}.");
-  EXPECT_EQ("The answer is 42.", prepared.format("answer", 42));
+  EXPECT_EQ("The answer is 42.", fmt::format(prepared, "answer", 42));
   prepared = fmt::compile<prepared_format>("40 {} 2 = {}");
-  EXPECT_EQ("40 + 2 = 42", prepared.format("+", 42));
+  EXPECT_EQ("40 + 2 = 42", fmt::format(prepared, "+", 42));
 }
 
 TEST(PrepareTest, UserProvidedPartsContainerUnderlyingContainer) {
@@ -494,9 +494,9 @@ TEST(PrepareTest, UserProvidedPartsContainerUnderlyingContainer) {
                                      int>::type prepared_format;
 
   prepared_format prepared = fmt::compile<prepared_format>("The {} is {}.");
-  EXPECT_EQ("The answer is 42.", prepared.format("answer", 42));
+  EXPECT_EQ("The answer is 42.", fmt::format(prepared, "answer", 42));
   prepared = fmt::compile<prepared_format>("40 {} 2 = {}");
-  EXPECT_EQ("40 + 2 = 42", prepared.format("+", 42));
+  EXPECT_EQ("40 + 2 = 42", fmt::format(prepared, "+", 42));
 }
 
 class custom_parts_container {
@@ -538,67 +538,67 @@ TEST(PrepareTest, UserProvidedPartsContainer) {
                                      std::string, int>::type prepared_format;
 
   prepared_format prepared = fmt::compile<prepared_format>("The {} is {}.");
-  EXPECT_EQ("The answer is 42.", prepared.format("answer", 42));
+  EXPECT_EQ("The answer is 42.", fmt::format(prepared, "answer", 42));
   prepared = fmt::compile<prepared_format>("40 {} 2 = {}");
-  EXPECT_EQ("40 + 2 = 42", prepared.format("+", 42));
+  EXPECT_EQ("40 + 2 = 42", fmt::format(prepared, "+", 42));
 }
 
 TEST(PrepareTest, PassConstCharPointerFormat) {
   const char* c_format = "test {}";
   const auto prepared = fmt::compile<int>(c_format);
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const wchar_t* wc_format = L"test {}";
   const auto wprepared = fmt::compile<int>(wc_format);
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 TEST(PrepareTest, PassCharArrayFormat) {
   char c_format[] = "test {}";
   const auto prepared = fmt::compile<int>(c_format);
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   wchar_t wc_format[] = L"test {}";
   const auto wprepared = fmt::compile<int>(wc_format);
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 TEST(PrepareTest, PassConstCharArrayFormat) {
   const char c_format[] = "test {}";
   const auto prepared = fmt::compile<int>(c_format);
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const wchar_t wc_format[] = L"test {}";
   const auto wprepared = fmt::compile<int>(wc_format);
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 TEST(PrepareTest, PassStringLiteralFormat) {
   const auto prepared = fmt::compile<int>("test {}");
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const auto wprepared = fmt::compile<int>(L"test {}");
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 TEST(PrepareTest, PassStringViewFormat) {
   const auto prepared =
       fmt::compile<int>(fmt::basic_string_view<char>("test {}"));
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const auto wprepared =
       fmt::compile<int>(fmt::basic_string_view<wchar_t>(L"test {}"));
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 TEST(PrepareTest, PassBasicStringFormat) {
   const auto prepared = fmt::compile<int>(std::string("test {}"));
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const auto wprepared = fmt::compile<int>(std::wstring(L"test {}"));
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 
 #if FMT_USE_CONSTEXPR
 TEST(PrepareTest, PassCompileString) {
   const auto prepared = fmt::compile<int>(FMT_STRING("test {}"));
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
   const auto wprepared = fmt::compile<int>(FMT_STRING(L"test {}"));
-  EXPECT_EQ(L"test 42", wprepared.format(42));
+  EXPECT_EQ(L"test 42", fmt::format(wprepared, 42));
 }
 #endif
 
@@ -637,7 +637,7 @@ TEST(PrepareTest, PassUserTypeFormat) {
   typedef std::basic_string<char, std::char_traits<char>, user_allocator<char>>
       user_format;
   const auto prepared = fmt::compile<int>(user_format("test {}"));
-  EXPECT_EQ("test 42", prepared.format(42));
+  EXPECT_EQ("test 42", fmt::format(prepared, 42));
 }
 
 TEST(PrepareTest, FormatToArrayOfChars) {