Static rustc_lint_defs::builtin::DEPRECATED_WHERE_CLAUSE_LOCATION

pub static DEPRECATED_WHERE_CLAUSE_LOCATION: &Lint

The deprecated_where_clause_location lint detects when a where clause in front of the equals in an associated type.

Example

trait Trait {
  type Assoc<'a> where Self: 'a;
}

impl Trait for () {
  type Assoc<'a> where Self: 'a = ();
}

{{produces}}

Explanation

The preferred location for where clauses on associated types in impls is after the type. However, for most of generic associated types development, it was only accepted before the equals. To provide a transition period and further evaluate this change, both are currently accepted. At some point in the future, this may be disallowed at an edition boundary; but, that is undecided currently.