Consider the following productions and the lookup rule in fun-untyped:
```syntax Name ::= Token{[a-z][\_a-zA-Z0-9]*}       [notInRules]```
```syntax Name ::= "$h"```
```
  rule <k> X:Name => V ...</k>
       <env>... X |-> L ...</env>
       <store>... L |-> V ...</store>
```

Name is a token sort thanks to the first production and, therefore, the lookup rule has a ```TokenIndex```. However, ```$h``` has a ```KLabelIndex``` and will get stuck when it appears on top of the k cell.