error: expected one of `>`, a const expression, lifetime, or type, found `,` --> $DIR/issue-20616-4.rs:16:34 | LL | type Type_4 = Type_1_<'static,, T>; | ^ expected one of `>`, a const expression, lifetime, or type | help: you might have meant to end the type parameters here | LL | type Type_4 = Type_1_<'static>,, T>; | + error: aborting due to 1 previous error