Implement println (#3267)

include/fmt/core.h

@@ -3009,6 +3009,36 @@ FMT_INLINE void print(std::FILE* f, format_string<T...> fmt, T&&... args) {
                            : detail::vprint_mojibake(f, fmt, vargs);
 }
 
+/**
+  \rst
+  Formats ``args`` according to specifications in ``fmt`` and writes the
+  output to the file ``f`` followed by a newline.
+
+  **Example**::
+
+       fmt::println(stderr, "Don't {}!", "panic");
+  \endrst
+ */
+template <typename... T>
+FMT_INLINE void println(std::FILE* f, format_string<T...> fmt, T&&... args) {
+  return fmt::print(f, "{}\n", fmt::format(fmt, std::forward<T>(args)...));
+}
+
+/**
+  \rst
+  Formats ``args`` according to specifications in ``fmt`` and writes the output
+  to ``stdout`` followed by a newline.
+
+  **Example**::
+
+       fmt::println("Elapsed time: {0:.2f} seconds", 1.23);
+  \endrst
+ */
+template <typename... T>
+FMT_INLINE void println(format_string<T...> fmt, T&&... args) {
+  return fmt::println(stdout, fmt, std::forward<T>(args)...);
+}
+
 FMT_MODULE_EXPORT_END
 FMT_GCC_PRAGMA("GCC pop_options")
 FMT_END_NAMESPACE