Macro syntax::walk_list

macro_rules! walk_list {
    ($visitor: expr, $method: ident, $list: expr) => { ... };
    ($visitor: expr, $method: ident, $list: expr, $($extra_args: expr),*) => { ... };
}

🔬 This is a nightly-only experimental API. (rustc_private)

this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via Cargo.toml instead?