diff --git a/lib/exec.c b/lib/exec.c
index b2a5f56..e7f9b9f 100644
--- a/lib/exec.c
+++ b/lib/exec.c
@@ -38,25 +38,7 @@ void exec_instr(struct exec* self,
     switch (instr->opcode)
     {
         case OP_CALL: {
-            MOKA fun = moka_pop(moka);
-            struct vec args;
-            vec_init(&args);
-
-            for (ssize_t i=0; i<param; i++)
-            {
-                MOKA arg = moka_pop(moka);
-                vec_push(&args, (void*) arg);
-            }
-
-            struct value* val = moka->global_values.data[
-                moka_get_ref(moka, fun)
-            ];
-
-            assert(val->type == TY_NATIVE);
-            struct native* native = val->data.native;
-            (native->fun)(moka, &args);
-
-            vec_free(&args);
+            moka_call(moka, param);
             self->pc++;
         } break;
 
diff --git a/lib/moka.c b/lib/moka.c
index 764831e..e959b35 100644
--- a/lib/moka.c
+++ b/lib/moka.c
@@ -149,6 +149,30 @@ void moka_dump(struct moka* self, MOKA value)
     abort();
 }
 
+MOKA moka_call(struct moka* self, int arg_count)
+{
+    MOKA fun = moka_pop(self);
+    struct vec args;
+    vec_init(&args);
+
+    for (ssize_t i=0; i<arg_count; i++)
+    {
+        MOKA arg = moka_pop(self);
+        vec_push(&args, (void*) arg);
+    }
+
+    struct value* val = self->global_values.data[
+        moka_get_ref(self, fun)
+    ];
+
+    assert(val->type == TY_NATIVE);
+    struct native* native = val->data.native;
+    (native->fun)(self, &args);
+
+    vec_free(&args);
+    return moka_top(self);
+}
+
 MOKA moka_push_int(struct moka* self, int value, int line)
 {
     assert(self);
@@ -305,6 +329,12 @@ native_fun_t moka_get_native(struct moka* self, MOKA value)
 MOKA moka_eval_lazy(struct moka* self, MOKA lazy_value)
 {
     assert(self);
+
+    if (!moka_is(self, lazy_value, TY_LAZY))
+    {
+        return lazy_value;
+    }
+
     struct node* node = moka_get_lazy(self, lazy_value);
 
     struct compiler compiler;
diff --git a/lib/moka.h b/lib/moka.h
index 2b6baf6..67223a0 100644
--- a/lib/moka.h
+++ b/lib/moka.h
@@ -39,6 +39,7 @@ TypeKind moka_type_of(struct moka* self, MOKA value);
 
 void moka_dump(struct moka* self, MOKA value);
 
+MOKA moka_call(struct moka* self, int arg_count);
 MOKA moka_push_int(struct moka* self, int value, int line);
 int moka_get_int(struct moka* self, MOKA value);