On Monday, 20 December 2021 at 18:12:35 UTC, Stanislav Blinov wrote:

Thanks!!! Finally I was able to do it! The code is the following (well not in my final project but it's a demonstration):

enum add_char(string c) =
  `if (stdout_index < STDOUT_BUF_LEN) {
    stdout_buffer[stdout_index++] =` ~ c ~ `;
    continue;
  } else {
    sys_write(1, stdout_buffer.ptr, cast(i32)stdout_index);
    stdout_index = 0;
    stdout_buffer[stdout_index++] =` ~ c ~ `;
    continue;
  }`;

void main() {
  mixin(add_char!(__traits(identifier, c)));
}

I don't know if there is another way to do it but this works for me. Also another thing that I want to ask is if the "mixin" is generated every time inside a loop and if there is a better way to do that?

You can see the "String mixins" section here for more details. Mixins are generated at compile time, so if you're referring to a string mixin inside a runtime loop, the code will not be generated every time the loop runs.