--- a/querytrans/src/lib.rs
+++ b/querytrans/src/lib.rs
@@ -1,5 +1,3 @@
-#![feature(iter_intersperse)]
-
 mod parser;
 mod display;
 mod transform;
--- a/querytrans/src/transform.rs
+++ b/querytrans/src/transform.rs
@@ -47,11 +47,14 @@
         .map(|s| Simple::Term(Term(s))).collect()
     ))
   } else {
-    Simple::Group(Group(
-      ss.into_iter()
-        .intersperse(String::from("OR"))
-        .map(|s| Simple::Term(Term(s))).collect()
-    ))
+    let mut terms = Vec::new();
+    for (i, s) in ss.into_iter().enumerate() {
+      if i > 0 {
+        terms.push(Simple::Term(Term(String::from("OR"))));
+      }
+      terms.push(Simple::Term(Term(s)));
+    }
+    Simple::Group(Group(terms))
   };
   vec![inner]
 }