An associated type binding was done outside of the type parameter declaration and where
clause. Erroneous code example:
pub trait Foo { type A; fn boo(&self) -> <Self as Foo>::A; } struct Bar; impl Foo for isize { type A = usize; fn boo(&self) -> usize { 42 } } fn baz<I>(x: &<I as Foo<A=Bar>>::A) {} // error: associated type bindings are not allowed here
To solve this error, please move the type bindings in the type parameter declaration:
# struct Bar; # trait Foo { type A; } fn baz<I: Foo<A=Bar>>(x: &<I as Foo>::A) {} // ok!
Or in the where
clause:
# struct Bar; # trait Foo { type A; } fn baz<I>(x: &<I as Foo>::A) where I: Foo<A=Bar> {}