diff --git a/momap/fromslice.go b/momap/fromslice.go
index ad6396b..e8f2786 100644
--- a/momap/fromslice.go
+++ b/momap/fromslice.go
@@ -28,3 +28,11 @@ func FromSliceWithError[T any, K comparable, V any](ts []T, fn func(t T) (K, V,
 	}
 	return kvs, nil
 }
+
+func IndexSlice[T any, K comparable](ts []T, fn func(t T) K) map[K]T {
+	m, _ := FromSliceWithError(ts, func(t T) (k K, _ T, _ error) {
+		k = fn(t)
+		return k, t, nil
+	})
+	return m
+}