Eliminate more warnings

Author: propensive

src/core/rudiments-core.scala

@@ -217,11 +217,11 @@ extension [ValueType](iterable: Iterable[ValueType])
 
 extension [ElemType](value: IArray[ElemType])
   inline def mutable(using Unsafe): Array[ElemType] = value.asMatchable.runtimeChecked match
-    case array: Array[ElemType] => array
+    case array: (Array[ElemType] @unchecked) => array
 
 extension [ElemType](array: Array[ElemType])
   def immutable(using Unsafe): IArray[ElemType] = array.runtimeChecked match
-    case array: IArray[ElemType] => array
+    case array: (IArray[ElemType] @unchecked) => array
 
   def snapshot(using ClassTag[ElemType]): IArray[ElemType] =
     val newArray = new Array[ElemType](array.length)

src/core/rudiments.Indexable.scala

@@ -32,7 +32,7 @@ object Indexable:
       type Result = ElementType
 
       def contains(array: IArray[ElementType], index: Ordinal): Boolean =
-        index.n0 >= 0 && index.n0 <= Ult.of(array.length).n0
+        index.n0 >= 0 && index.n0 <= Ult.of(array).n0
 
       def access(array: IArray[ElementType], index: Ordinal): Result = array(index.n0)
 
@@ -43,7 +43,7 @@ object Indexable:
       type Result = ElementType
 
       def contains(seq: IndexedSeq[ElementType], index: Ordinal): Boolean =
-        index.n0 >= 0 && index.n0 <= Ult.of(seq.length).n0
+        index.n0 >= 0 && index.n0 <= Ult.of(seq).n0
 
       def access(seq: IndexedSeq[ElementType], index: Ordinal): Result = seq(index.n0)
 
@@ -53,7 +53,7 @@ object Indexable:
     type Result = Char
 
     def contains(text: Text, index: Ordinal): Boolean =
-      index.n0 >= 0 && index.n0 <= Ult.of(text).n0
+      index.n0 >= 0 && index.n0 < text.s.length
 
     def access(text: Text, index: Ordinal): Result = text.s.charAt(index.n0)