struct
  cell% field list-val
  cell% field list-next
end-struct list%

: new-list { list1 val -- list2 }
  list% %allot { list2 }
  list1 list2 list-next !
  val   list2 list-val  ! 
  list2 ;

: .list ( list -- )
  begin { l }
    l while
      l list-val @ .
      l list-next @
  repeat ;

: insert { val listp -- }
  listp @ val new-list listp ! ;

: member? { key liste -- flag }
  liste begin { l }
    l while
      l list-val @ key = if
        true exit endif
      l list-next @
  repeat 
  false ;

: search { key listp -- listp2 }
  listp begin { lp }
    lp @ while
      lp @ list-val @ key = if
        lp exit endif
      lp @ list-next
  repeat
  lp ;

cell% %allot constant listp
0 3 new-list
  1 new-list
listp !
cr listp @ .list

5 listp @ list-next insert
cr listp @ .list

7 listp insert
cr listp @ .list

8 5 listp search insert
cr listp @ .list