Add Slice to TypeName

Author: nathanwhit

chalk-ir/src/debug.rs

@@ -144,6 +144,7 @@ impl<I: Interner> Debug for TypeName<I> {
             TypeName::Scalar(scalar) => write!(fmt, "{:?}", scalar),
             TypeName::Tuple(arity) => write!(fmt, "{:?}", arity),
             TypeName::OpaqueType(opaque_ty) => write!(fmt, "!{:?}", opaque_ty),
+            TypeName::Slice => write!(fmt, "{{slice}}"),
             TypeName::Raw(mutability) => write!(fmt, "{:?}", mutability),
             TypeName::Ref(mutability) => write!(fmt, "{:?}", mutability),
             TypeName::Error => write!(fmt, "{{error}}"),

chalk-ir/src/lib.rs

@@ -156,6 +156,9 @@ pub enum TypeName<I: Interner> {
     /// a tuple of the given arity
     Tuple(usize),
 
+    /// a slice type like `[T]`
+    Slice,
+
     /// a raw pointer type like `*const T` or `*mut T`
     Raw(Mutability),
 

chalk-solve/src/clauses.rs

@@ -410,6 +410,7 @@ fn match_type_name<I: Interner>(
         TypeName::Tuple(_) => {
             builder.push_fact(WellFormed::Ty(application.clone().intern(interner)))
         }
+        TypeName::Slice => builder.push_fact(WellFormed::Ty(application.clone().intern(interner))),
         TypeName::Raw(_) => builder.push_fact(WellFormed::Ty(application.clone().intern(interner))),
         TypeName::Ref(_) => builder.push_fact(WellFormed::Ty(application.clone().intern(interner))),
     }