start -> expr [SimNode]
  expr -> assign-expr [SimNode]
    assign-expr -> or-expr assign-op assign-expr [SimNode]
      or-expr -> and-expr [SimNode]
        and-expr -> eq-expr [SimNode]
          eq-expr -> rel-expr [SimNode]
            rel-expr -> shift-expr [SimNode]
              shift-expr -> add-expr [SimNode]
                add-expr -> mul-expr [SimNode]
                  mul-expr -> unary-expr [SimNode]
                    unary-expr -> primary-expr [SimNode]
                      primary-expr -> IDENT [SimNode]
                        IDENT
      assign-op -> ASSIGN [SimNode]
        ASSIGN
      assign-expr -> or-expr [SimNode]
        or-expr -> and-expr [SimNode]
          and-expr -> eq-expr [SimNode]
            eq-expr -> rel-expr [SimNode]
              rel-expr -> shift-expr [SimNode]
                shift-expr -> shift-expr shift-op add-expr [SimNode]
                  shift-expr -> add-expr [SimNode]
                    add-expr -> mul-expr [SimNode]
                      mul-expr -> unary-expr [SimNode]
                        unary-expr -> primary-expr [SimNode]
                          primary-expr -> NUMBER [SimNode]
                            NUMBER
                  shift-op -> LSHIFT [SimNode]
                    LSHIFT
                  add-expr -> add-expr add-op mul-expr [SimNode]
                    add-expr -> mul-expr [SimNode]
                      mul-expr -> unary-expr [SimNode]
                        unary-expr -> primary-expr [SimNode]
                          primary-expr -> NUMBER [SimNode]
                            NUMBER
                    add-op -> PLUS [SimNode]
                      PLUS
                    mul-expr -> mul-expr mul-op unary-expr [SimNode]
                      mul-expr -> unary-expr [SimNode]
                        unary-expr -> primary-expr [SimNode]
                          primary-expr -> NUMBER [SimNode]
                            NUMBER
                      mul-op -> TIMES [SimNode]
                        TIMES
                      unary-expr -> primary-expr [SimNode]
                        primary-expr -> NUMBER [SimNode]
                          NUMBER