text: #pragma once
  
  #include "namespace.h"
  
  LSTD_BEGIN_NAMESPACE
  
  struct fmt_context;
  
  // Specialize this function for formatting a custom type.
  template <typename T>
  void write_custom(fmt_context *f, const T *t) {
      static_assert(false, "Argument doesn't have a way to be formatted.");
      assert(false);
  
      // e.g.
      // void write_custom(fmt_context *f, const my_vector *value) {
      //     fmt_to_writer(f, "x: {}, y: {}", value->x, value->y);
      //     // ...
      // }
  
      // If you already specialized but still get an error,
      // check if your implementation is in the library namespace.
  }
  
  LSTD_END_NAMESPACE
  