Add Array to TypeName

Author: nathanwhit

chalk-ir/src/debug.rs

@@ -168,6 +168,7 @@ impl<I: Interner> Debug for TypeName<I> {
             TypeName::Raw(mutability) => write!(fmt, "{:?}", mutability),
             TypeName::Ref(mutability) => write!(fmt, "{:?}", mutability),
             TypeName::Never => write!(fmt, "Never"),
+            TypeName::Array => write!(fmt, "{{array}}"),
             TypeName::Error => write!(fmt, "{{error}}"),
         }
     }

chalk-ir/src/lib.rs

@@ -157,6 +157,9 @@ pub enum TypeName<I: Interner> {
     /// a tuple of the given arity
     Tuple(usize),
 
+    /// an array type like `[T; N]`
+    Array,
+
     /// a slice type like `[T]`
     Slice,
 

chalk-solve/src/clauses.rs

@@ -421,6 +421,7 @@ fn match_type_name<I: Interner>(
         | TypeName::Slice
         | TypeName::Raw(_)
         | TypeName::Ref(_)
+        | TypeName::Array
         | TypeName::Never => {
             builder.push_fact(WellFormed::Ty(application.clone().intern(interner)))
         }