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Comment by twoodfin | Hacker News Reader

I don’t think the implication is that the C compiler must encode the binary file as a comma-separated integer list and then re-parse it, only act as if it did so.

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How would that work? It would need to depend on the grammar of surrounding C code. This directive isn't limited to variable initialisers. You can use it anywhere. So e.g. you can use it inside structure declaration, or between "int main()" and "{". etc. etc. Those will generate errors in subsequent phases, but during preprocessing the compiler doesn't know about it. Then there is also just that:

  int main () {
      return
  #embed "file.bin"
      ;
  }

There are plenty of cases, where it will all behave differently. And if you're going to pretend even more that the preprocessor understands C syntax, then why not just give this job to compiler proper, which actually understands it?

Preprocessing produces a series of tokens, so you would implement it as a new type of token. If you're using something like `-E` you would just pretty-print it as a comma-delimited list of integers. If you're moving on to translation phase 7, you'd have some sort of rules in your parser about where those kinds of tokens can appear . Just like you can't have a return token in an initializer, you wouldn't be allowed to have an embed token outside of one (or whatever the rules are). And you can directly instantiate some kind of node that contains the binary data.

> you would implement it as a new type of token

That's a good point. I consider myself debunked.

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