rust/src/test/compile-fail/regions-infer-invariance-due-to-arg-and-ret.rs

// Invariance with respect to a region:
//
// You cannot convert between regions.

struct invariant {
    f: fn(x: &self/int) -> &self/int
}

fn to_same_lifetime(bi: invariant/&r) {
    let bj: invariant/&r = bi;
}

fn to_shorter_lifetime(bi: invariant/&r) {
    let bj: invariant/&blk = bi; //~ ERROR mismatched types
}

fn to_longer_lifetime(bi: invariant/&r) -> invariant/&static {
    bi //~ ERROR mismatched types
}

fn main() {
}