skip peek
skip consume
skip next
skip is
skip fzl_mknode
skip fzl_mktoken
skip fzl_symt_put
skip fzl_symt_get
skip add_const
skip push_op
skip push_word
skip fzl_mkenv
skip fzl_freeenv
skip fzl_env_lookup
skip fzl_env_contains
skip fzl_env_storevalue
skip fzl_env_writevalue