diff --git a/crates/prolog_parser/src/ast.rs b/crates/prolog_parser/src/ast.rs
index 37c98b55..fcde5b5a 100644
--- a/crates/prolog_parser/src/ast.rs
+++ b/crates/prolog_parser/src/ast.rs
@@ -1,6 +1,6 @@
+use crate::rug::{Integer, Rational};
 use crate::tabled_rc::*;
 use ordered_float::*;
-use rug::{Integer, Rational};
 
 use crate::put_back_n::*;