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# Error code E0688

#### Note: this error code is no longer emitted by the compiler.

In-band lifetimes were mixed with explicit lifetime binders.

Erroneous code example:

    #![feature(in_band_lifetimes)]

    fn foo<'a>(x: &'a u32, y: &'b u32) {}   // error!

    struct Foo<'a> { x: &'a u32 }

    impl Foo<'a> {
        fn bar<'b>(x: &'a u32, y: &'b u32, z: &'c u32) {}   // error!
    }

    impl<'b> Foo<'a> {  // error!
        fn baz() {}
    }

In-band lifetimes cannot be mixed with explicit lifetime binders. For example:

    #![allow(unused)]
    fn main() {
    fn foo<'a, 'b>(x: &'a u32, y: &'b u32) {}   // ok!

    struct Foo<'a> { x: &'a u32 }

    impl<'a> Foo<'a> {
        fn bar<'b,'c>(x: &'a u32, y: &'b u32, z: &'c u32) {}    // ok!
    }

    impl<'a> Foo<'a> {  // ok!
        fn baz() {}
    }
    }