Code sample from the docs generates deprecated warning

[alighazi]

I copy pasted the code sample from: Formatting user-defined types¶ and customized it for my own type. but it seems like ctx.begin() is marked as deprecated, what should be used instead?

this is my code

namespace fmt{
template <>
struct formatter<glm::ivec2> {
  template <typename ParseContext>
  constexpr auto parse(ParseContext &ctx) { return ctx.begin(); }

  template <typename FormatContext>
  auto format(const glm::ivec2 &r, FormatContext &ctx) {
    return format_to(ctx.begin(), "x: {}, y: {}", r.x, r.y);
  }
};

}

and this is the generated warning:

[build] /home/jizz/code/gl/chetris/include/core/util/to_string.hpp: In instantiation of ‘auto fmt::v5::formatter<glm::vec<2, int, (glm::qualifier)0> >::format(const ivec2&, FormatContext&) [with FormatContext = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>; glm::ivec2 = glm::vec<2, int, (glm::qualifier)0>]’:
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:751:5:   required from ‘static void fmt::v5::internal::value<Context>::format_custom_arg(const void*, fmt::v5::basic_parse_context<typename Context::char_type>&, Context&) [with T = glm::vec<2, int, (glm::qualifier)0>; Formatter = fmt::v5::formatter<glm::vec<2, int, (glm::qualifier)0> >; Context = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>; typename Context::char_type = char]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:732:19:   required from ‘fmt::v5::internal::value<Context>::value(const T&) [with T = glm::vec<2, int, (glm::qualifier)0>; Context = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:761:58:   required from ‘constexpr fmt::v5::internal::init<Context, T, TYPE>::operator fmt::v5::internal::value<Context>() const [with Context = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>; T = const glm::vec<2, int, (glm::qualifier)0>&; fmt::v5::internal::type TYPE = (fmt::v5::internal::type)13]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:1080:35:   required from ‘fmt::v5::internal::value<Context> fmt::v5::internal::make_arg(const T&) [with bool IS_PACKED = true; Context = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>; T = glm::vec<2, int, (glm::qualifier)0>; typename std::enable_if<IS_PACKED, int>::type <anonymous> = 0]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:1196:53:   required from ‘fmt::v5::format_arg_store<Context, Args>::format_arg_store(const Args& ...) [with Context = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>; Args = {glm::vec<2, int, (glm::qualifier)0>}]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:1374:18:   required from ‘fmt::v5::format_arg_store<typename fmt::v5::buffer_context<typename fmt::v5::internal::char_t<S>::type>::type, Args ...> fmt::v5::internal::make_args_checked(const S&, const Args& ...) [with S = char [15]; Args = {glm::vec<2, int, (glm::qualifier)0>}; typename std::enable_if<fmt::v5::internal::is_string<S>::value, int>::type <anonymous> = 0; typename fmt::v5::buffer_context<typename fmt::v5::internal::char_t<S>::type>::type = fmt::v5::basic_format_context<std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >, char>]’
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:1504:37:   required from ‘void fmt::v5::print(const S&, const Args& ...) [with S = char [15]; Args = {glm::vec<2, int, (glm::qualifier)0>}; typename std::enable_if<fmt::v5::internal::is_string<S>::value, int>::type <anonymous> = 0]’
[build] /home/jizz/code/gl/chetris/src/core/c_block.cpp:15:43:   required from here
[build] /home/jizz/code/gl/chetris/include/core/util/to_string.hpp:77:21: warning: ‘fmt::v5::basic_format_context<OutputIt, Char>::iterator fmt::v5::basic_format_context<OutputIt, Char>::begin() [with OutputIt = std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >; Char = char; fmt::v5::basic_format_context<OutputIt, Char>::iterator = std::back_insert_iterator<fmt::v5::internal::basic_buffer<char> >]’ is deprecated [-Wdeprecated-declarations]
[build]      return format_to(ctx.begin(), "x: {}, y: {}", r.x, r.y);
[build]             ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[build] In file included from /home/jizz/code/gl/chetris/include/core/common.hpp:12:0,
[build]                  from /home/jizz/code/gl/chetris/include/core/ecs/c_block.hpp:2,
[build]                  from /home/jizz/code/gl/chetris/src/core/c_block.cpp:1:
[build] /home/jizz/code/gl/chetris/vendor/fmt/include/fmt/core.h:1134:27: note: declared here
[build]    FMT_DEPRECATED iterator begin() { return out_; }

You should be using out() instead.

return format_to(ctx.out(), "({:.1f}, {:.1f})", p.x, p.y);

[alighazi]

Thanks 👍