iter-ops raised above assign; 'cat' operator returns an iterator; $$ operator supports iterators producing a list of items

t_iterator_test.go

@@ -49,3 +49,14 @@ func TestIteratorParser(t *testing.T) {
 	// runTestSuiteSpec(t, section, inputs, 10)
 	runTestSuite(t, section, inputs)
 }
+
+func TestCatIterator(t *testing.T) {
+	section := "Iterator"
+	inputs := []inputType{
+		/*   1 */ {`([1] cat [2]) map $_`, kern.NewList([]any{int64(1), int64(2)}), nil},
+		/*   2 */ {`$$([1] cat [2])`, kern.NewList([]any{int64(1), int64(2)}), nil},
+	}
+
+	// runTestSuiteSpec(t, section, inputs, 2)
+	runTestSuite(t, section, inputs)
+}