diff -r ea2d1e40d707 -r 7a1f1f6f34b5 src/sets.rs
--- a/src/sets.rs	Sun Jul 12 11:29:06 2026 +0300
+++ b/src/sets.rs	Sat Aug 01 23:33:44 2026 -0500
@@ -35,8 +35,9 @@
 where
     U: Num + PartialOrd + Sized,
 {
+    #[inline]
     fn contains<I: Instance<Loc<N, U>>>(&self, item: I) -> bool {
-        item.eval_ref(|r| self.0.iter().zip(r.iter()).all(|(s, x)| s.contains(x)))
+        item.eval_ref(|r| self.0.iter().zip(r.iter()).all(|([a, b], x)| a<=x && x<=b))
     }
 }