[][src]Function rustc::ty::tls::with_context_opt

pub fn with_context_opt<F, R>(f: F) -> R where
    F: for<'a, 'gcx, 'tcx> FnOnce(Option<&ImplicitCtxt<'a, 'gcx, 'tcx>>) -> R, 
🔬 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?

Allows access to the current ImplicitCtxt in a closure if one is available