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// Test that a type which is covariant with respect to its region
// parameter yields an error when used in a contravariant way.
//
// Note: see variance-regions-*.rs for the tests that check that the
// variance inference works in the first place.
// `S` is contravariant with respect to both parameters.
struct S<'a, 'b> {
f: &'a isize,
g: &'b isize,
}
fn use_<'short,'long>(c: S<'long, 'short>,
s: &'short isize,
l: &'long isize,
_where:Option<&'short &'long ()>) {
let _: S<'long, 'short> = c; // OK
let _: S<'short, 'short> = c; // OK
// Test whether S<_,'short> <: S<_,'long>. Since
// 'short <= 'long, this would be true if the Contravariant type were
// covariant with respect to its parameter 'a.
let _: S<'long, 'long> = c;
//~^ ERROR lifetime may not live long enough
}
fn main() {}
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