Function syntax::ext::base::expr_to_string

pub fn expr_to_string(
    cx: &mut ExtCtxt, 
    expr: P<Expr>, 
    err_msg: &str
) -> Option<(Symbol, StrStyle)>

🔬 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?