[−][src]Function syntax::ext::tt::macro_rules::check_lhs_no_empty_seq
fn check_lhs_no_empty_seq(sess: &ParseSess, tts: &[TokenTree]) -> bool
🔬 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?
Check that the lhs contains no repetition which could match an empty token tree, because then the matcher would hang indefinitely.