| MQUse (alist, asvar) ->
use_ex (execute_ex env alist) asvar "B" (*"backPointer"*)
| MQPattern (apreamble, apattern, afragid) ->
| MQUse (alist, asvar) ->
use_ex (execute_ex env alist) asvar "B" (*"backPointer"*)
| MQPattern (apreamble, apattern, afragid) ->