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An associated item constraint was written in an unexpected context.
Erroneous code example:
```compile_fail,E0229
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 item constraint are not allowed here
```
To solve this error, please move the associated item constraints to the type
parameter declaration:
```
# struct Bar;
# trait Foo { type A; }
fn baz<I: Foo<A=Bar>>(x: &<I as Foo>::A) {} // ok!
```
Or into the where-clause:
```
# struct Bar;
# trait Foo { type A; }
fn baz<I>(x: &<I as Foo>::A) where I: Foo<A=Bar> {}
```
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