Module with_builtin_macros::builtin_macros::include_from_root

See the stdlib documentation.

The difference between ::core::include! and this version of the macro is that, due to limitations of proc-macros in stable Rust, it is not possible to know whence a macro is called.

Thus, this macro requires it be called with a path that starts from the “root” of the package, i.e., a path that will be interpreted as if it started from: concat!(env!("CARGO_MANIFEST_DIR"), "/").

Example

use ::with_builtin_macros::with_builtin;

macro_rules! metamancy {(
    $use_stmt:item

    $macro_def_item:item

    #[cfg(any())]
    mod to_be_expanded { $foo_fn:item }

    $main_fn:item

    $macro_call:item
) => (
    $foo_fn
)}

#[cfg(any())]
mod to_be_expanded {
    fn foo ()
    {}
}

fn main ()
{
    foo();
}

with_builtin!(let $this_file = include_from_root!("src/main.rs") in {
    metamancy!($this_file);
});