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This post is auto-generated from RSS feed The Rust Programming Language Forum - Latest topics. Source: Self not recognized in blocks macro parameters

Hi!
I'm currently trying to create a macro that involves having as a parameter the block of a function,
as in this example:

macro_rules! implement {
    (
        $name:ty,
        fn $func:ident(&self) $block:block
    ) => {
        impl $name {
            fn $func(&self) $block
        }
    }
}

struct Foo {
    bar: i32,
}
implement! {
    Foo,
    fn print_bar(&self) {
        println!("bar: {}", self.bar);
    }
}

even though cargo expand's shows the correct expansion (which includes &self in the function signature), this code doesn't compile.. The compiler gives this error:

expected value, found module `self` [E0424]
`self` value is a keyword only available in methods with a `self` parameter

So, I wanted to ask:

• Is this behavior expected, or am I doing something wrong?
• Are there any plans to make this work in the future? (e.g. with the new macro syntax)
• What would be a valid workaround here?
  Thanks!

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