diff --git a/compile.c b/compile.c
index a0069b3..775c17d 100644
--- a/compile.c
+++ b/compile.c
@@ -278,9 +278,20 @@ CORD compile_type(type_t *t)
 static CORD compile_lvalue(env_t *env, ast_t *ast)
 {
     if (!can_be_mutated(env, ast)) {
-        if (ast->tag == Index || ast->tag == FieldAccess) {
-            ast_t *subject = ast->tag == Index ? Match(ast, Index)->indexed : Match(ast, FieldAccess)->fielded;
-            code_err(subject, "This is an immutable value, you can't assign to it");
+        if (ast->tag == Index) {
+            ast_t *subject = Match(ast, Index)->indexed;
+            type_t *t = get_type(env, subject);
+            if (t->tag == PointerType && Match(t, PointerType)->is_view)
+                code_err(ast, "This is a read-only view and you can't mutate its contents");
+            else
+                code_err(subject, "This is an immutable value, you can't mutate its contents");
+        } else if (ast->tag == FieldAccess) {
+            ast_t *subject = Match(ast, FieldAccess)->fielded;
+            type_t *t = get_type(env, subject);
+            if (t->tag == PointerType && Match(t, PointerType)->is_view)
+                code_err(subject, "This is a read-only view and you can't mutate its fields");
+            else
+                code_err(subject, "This is an immutable value, you can't assign to its fields");
         } else {
             code_err(ast, "This is a value of type %T and can't be used as an assignment target", get_type(env, ast));
         }
diff --git a/typecheck.c b/typecheck.c
index ceefda1..6cc4121 100644
--- a/typecheck.c
+++ b/typecheck.c
@@ -1293,7 +1293,7 @@ PUREFUNC bool can_be_mutated(env_t *env, ast_t *ast)
         auto index = Match(ast, Index);
         type_t *indexed_type = get_type(env, index->indexed);
         if (indexed_type->tag == PointerType)
-            return true;
+            return !Match(indexed_type, PointerType)->is_view;
         return can_be_mutated(env, index->indexed);
     }
     default: return false;