Lifetime bounds of associated functions

help
#1

The following example:

struct A<'a, T>(&'a T);

impl<'a, T> A<'a, T>
where T: PartialOrd {
    fn lt(x: &T, a: &T) -> bool { x < a }

    fn f(x: &T) -> bool { Self::lt(x, x) }
}

does not compile. It looks like using Self::lt induces a dependency on the lifetime of A. If I use an “external” function:

fn lt<T: PartialOrd>(x: &T, a: &T) -> bool { x < a }

and define f as

    fn f(x: &T) -> bool { lt(x, x) }

it works. Why is there a different treatment for associated functions? (I would prefer to use these as they better point to the fact that lt will only be used locally.)

Thanks for your help.

#2

Looks like a bug. The bound T: 'a should be implied. If I specify it explicitly it works:

- impl<'a, T> A<'a, T>
+ impl<'a, T: 'a> A<'a, T>
  where
      T: PartialOrd,
  {
#3

Thanks.

Looks like a bug. The bound T: 'a should be implied.

Ah, that would explain that I have other associated functions taking &T which did not require the T: 'a bound.

#4

I think it is:

#5

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