diff --git a/nac3core/src/codegen/object/list.rs b/nac3core/src/codegen/object/list.rs
index 77a075da..dad5b7fd 100644
--- a/nac3core/src/codegen/object/list.rs
+++ b/nac3core/src/codegen/object/list.rs
@@ -65,6 +65,11 @@ impl<'ctx> ListObject<'ctx> {
         ListObject { item_type, instance: value }
     }
 
+    /// Check if an object can be converted into an ndarray.
+    pub fn is_instance(ctx: &mut CodeGenContext<'ctx, '_>, object: AnyObject<'ctx>) -> bool {
+        matches!(&*ctx.unifier.get_ty(object.ty), TypeEnum::TObj { obj_id, .. } if *obj_id == ctx.primitives.list.obj_id(&ctx.unifier).unwrap())
+    }
+
     /// Get the `len()` of this list.
     pub fn len<G: CodeGenerator + ?Sized>(
         &self,
diff --git a/nac3core/src/codegen/object/ndarray/mod.rs b/nac3core/src/codegen/object/ndarray/mod.rs
index f3ac96a0..99849451 100644
--- a/nac3core/src/codegen/object/ndarray/mod.rs
+++ b/nac3core/src/codegen/object/ndarray/mod.rs
@@ -13,7 +13,7 @@ use crate::{
         CodeGenContext, CodeGenerator,
     },
     toplevel::{helper::extract_ndims, numpy::unpack_ndarray_var_tys},
-    typecheck::typedef::Type,
+    typecheck::typedef::{Type, TypeEnum},
 };
 
 use super::any::AnyObject;
@@ -69,6 +69,11 @@ impl<'ctx> NDArrayObject<'ctx> {
         NDArrayObject { dtype, ndims, instance: value }
     }
 
+    /// Check if an object can be converted into an ndarray.
+    pub fn is_instance(ctx: &mut CodeGenContext<'ctx, '_>, object: AnyObject<'ctx>) -> bool {
+        matches!(&*ctx.unifier.get_ty(object.ty), TypeEnum::TObj { obj_id, .. } if *obj_id == ctx.primitives.ndarray.obj_id(&ctx.unifier).unwrap())
+    }
+
     /// Get this ndarray's `ndims` as an LLVM constant.
     pub fn ndims_llvm<G: CodeGenerator + ?Sized>(
         &self,
diff --git a/nac3core/src/codegen/object/tuple.rs b/nac3core/src/codegen/object/tuple.rs
index 00e52a7e..792e5aca 100644
--- a/nac3core/src/codegen/object/tuple.rs
+++ b/nac3core/src/codegen/object/tuple.rs
@@ -44,6 +44,11 @@ impl<'ctx> TupleObject<'ctx> {
         TupleObject { tys: tys.clone(), value }
     }
 
+    /// Check if an object can be converted into a tuple.
+    pub fn is_instance(ctx: &mut CodeGenContext<'ctx, '_>, object: AnyObject<'ctx>) -> bool {
+        matches!(&*ctx.unifier.get_ty(object.ty), TypeEnum::TTuple { .. })
+    }
+
     /// Convenience function. Create a [`TupleObject`] from an iterator of objects.
     pub fn from_objects<I, G: CodeGenerator + ?Sized>(
         generator: &mut G,