diff --git a/src/cat.ts b/src/cat.ts
index 10195ad..48e9fbc 100644
--- a/src/cat.ts
+++ b/src/cat.ts
@@ -288,8 +288,8 @@ export const Primitives: Environment<any> = {
 
     '?'(n, vs) { return [(vs as Value<any>[])[n as number]]; },
     'length'(a) { return [(a as Value<any>[]).length]; },
-    'save'() { return [this.take(this.stack.length)]; },
-    'restore'(vs) { return (vs as Value<any>[]); },
+    'saveStack'() { return [this.take(this.stack.length)]; },
+    'restoreStack'(vs) { return (vs as Value<any>[]); },
     'untake'(vs) { (vs as Value<any>[]).push((vs as Value<any>[]).length); return (vs as Value<any>[]); },
 
     'not'(v) { return [!v]; },
@@ -329,6 +329,6 @@ Object.assign(Primitives, {
 // R('[1 - dup 0 lt [drop] [dup x] ifelse] to x 5 x')
 // R('[1 - dup 0 lt [drop] [dup to v x v] ifelse] to x 5 x')
 // R('[3] 5 times');
-// R('2 3 4 save [2 *] map restore');
-// R('20 iota [dup 3 % 0 eq [1 take] [drop 0 take] ifelse] flatMap restore');
-// R('20 iota [3 % 0 eq] filter restore');
+// R('2 3 4 saveStack [2 *] map restoreStack');
+// R('20 iota [dup 3 % 0 eq [1 take] [drop 0 take] ifelse] flatMap restoreStack');
+// R('20 iota [3 % 0 eq] filter restoreStack');