How to fix "argument must be a string literal" with include_bytes!()?

Question

I want to compile this test file but I am getting an error:

const TEST: &'static str = "Test.bin";

fn main() {
    let x = include_bytes!(TEST);
}

error: argument must be a string literal
 --> test.rs:4:22
  |
4 |     let x = include_bytes!(TEST);
  |                      ^^^^

How to fix this?

Answer 1

The macro expects a string literal, so it cannot be a variable:

include_bytes!("Test.bin");

Alternatively you could create a macro that will expand into the desired value too:

macro_rules! test_bin {
    // `()` indicates that the macro takes no argument.
    () => {
        "Test.bin"
    };
}

fn main() {
    let x = include_bytes!(test_bin!());
}

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