food-chain: fix (#186)

bin/test

@@ -59,11 +59,6 @@ done
 for practice_exercise_dir in ./exercises/practice/*/; do
     if [[ -d $practice_exercise_dir ]]; then
         echo "Checking $(basename "${practice_exercise_dir}") exercise..."        
-        # TODO: re-enable once the example solution to food-chain is fixed
-        if [[ $(basename "${practice_exercise_dir}") == "food-chain" ]]; then
-            echo "$(basename "${practice_exercise_dir}"): skipped"
-            continue
-        fi
         verify_exercise "$practice_exercise_dir" "example"
     fi
 done

exercises/practice/food-chain/.meta/example.8th

@@ -42,12 +42,13 @@
 : verse \ n -- a
   dup a:new 
   swap verse-start a:+ 
+  over 8 n:= if nip ;then
   swap verse-middle a:+
   verse-end a:push
 ;
 
 : join-verses \ a -- a
-  ( swap a:len 0 n:= !if "" a:push then swap a:+ ) [] a:reduce
+  ( swap a:len 0 n:= !if "" a:push then swap a:+ ) a:new a:reduce
 ;
 
 : recite \ n n -- a