| 31 | |
| 32 | template <typename ...Tokens> |
| 33 | constexpr auto format(Tokens ...tokens_) { |
| 34 | auto tokens = hana::make_tuple(tokens_...); |
| 35 | |
| 36 | // If you don't care about constexpr-ness of `format`, you can use |
| 37 | // this lambda instead of `compose(partial(...), typeid_)`: |
| 38 | // |
| 39 | // [](auto token) { |
| 40 | // return formats[typeid_(token)]; |
| 41 | // } |
| 42 | auto format_string_tokens = hana::adjust_if(tokens, |
| 43 | hana::compose(hana::not_, hana::is_a<hana::string_tag>), |
| 44 | hana::compose(hana::partial(hana::at_key, formats), hana::typeid_) |
| 45 | ); |
| 46 | |
| 47 | auto format_string = hana::sum<hana::string_tag>(format_string_tokens); |
| 48 | auto variables = hana::filter(tokens, hana::compose(hana::not_, hana::is_a<hana::string_tag>)); |
| 49 | return hana::prepend(variables, format_string); |
| 50 | } |
| 51 | |
| 52 | int main() { |
| 53 | int a = 1; |