Swift: QLDoc getCanonicalType.

swift/schema.py

@@ -77,7 +77,13 @@ class AstNode(Locatable):
 @ql.hideable
 class Type(Element):
     name: string
-    canonical_type: "Type"
+    canonical_type: "Type" | desc("""
+        This is the unique type we get after resolving aliases and desugaring. For example, given
+        ```
+        typealias MyInt == Int
+        ```
+        then `[MyInt?]` has the canonical type `Array<Optional<Int>>`.
+    """)
 
 @group("decl")
 class Decl(AstNode):