1 files changed, 13 insertions, 0 deletions
diff --git a/src/utils.js b/src/utils.js
index 2c3ea72..e1725ef 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -38,7 +38,20 @@ const keys = (ks, obj) =>
 		{},
 	);
 
+const difference = (a, b) => {
+	const diff = new Set(a);
+	for (const el of b) {
+		diff.delete(el);
+	}
+	return diff;
+};
+
+const log = o => console.error(JSON.stringify(o));
+
+
 module.exports = {
 	eq,
 	keys,
+	difference,
+	log,
 };