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// Test that we invoking `foo()` successfully resolves to the trait `Foo`
// (prompting the mismatched types error) but does not influence the choice
// of what kind of `Vec` we have, eventually leading to a type error.
trait Foo {
fn foo(&self) -> isize;
}
impl Foo for Vec<usize> {
fn foo(&self) -> isize {1}
}
impl Foo for Vec<isize> {
fn foo(&self) -> isize {2}
}
// This is very hokey: we have heuristics to suppress messages about
// type annotations needed. But placing these two bits of code into
// distinct functions, in this order, causes us to print out both
// errors I'd like to see.
fn m1() {
// we couldn't infer the type of the vector just based on calling foo()...
let mut x = Vec::new();
//~^ ERROR type annotations needed
x.foo(); //~ ERROR type annotations needed
}
fn m2() {
let mut x = Vec::new();
// ...but we still resolved `foo()` to the trait and hence know the return type.
let y: usize = x.foo(); //~ ERROR mismatched types
}
fn main() { }
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