diff --git a/docs/string.md b/docs/string.md
index 97b3ddc..3a3d785 100644
--- a/docs/string.md
+++ b/docs/string.md
@@ -505,11 +505,10 @@ function passthru(literals) {
   let i = 0;
 
   while (i < literals.length) {
-    result += literals[i];
+    result += literals[i++];
     if (i < arguments.length) {
       result += arguments[i];
     }
-    i++;
   }
 
   return result;