Static rustc_lint::builtin::INDIRECT_STRUCTURAL_MATCH

source ·
pub static INDIRECT_STRUCTURAL_MATCH: &'static Lint
Expand description

The indirect_structural_match lint detects a const in a pattern that manually implements PartialEq and Eq.

§Example

#![deny(indirect_structural_match)]

struct NoDerive(i32);
impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
impl Eq for NoDerive { }
#[derive(PartialEq, Eq)]
struct WrapParam<T>(T);
const WRAP_INDIRECT_PARAM: & &WrapParam<NoDerive> = & &WrapParam(NoDerive(0));
fn main() {
    match WRAP_INDIRECT_PARAM {
        WRAP_INDIRECT_PARAM => { }
        _ => { }
    }
}

{{produces}}

§Explanation

The compiler unintentionally accepted this form in the past. This is a future-incompatible lint to transition this to a hard error in the future. See issue #62411 for a complete description of the problem, and some possible solutions.