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