anchor.diff:  -define( FilterFuns, 
               [ list, prefix_ul, concat, is_nav, is_val, is_key 
               , is_member, is_like, is_regexp_like, to_name, to_text
  -            , add_dt, add_ts, diff_dt, diff_ts, list_to_tuple
  +            , add_dt, add_ts, diff_dt, diff_ts, list_to_tuple, list_to_binstr
               , to_atom, to_string, to_binstr, to_binary, to_integer, to_float, to_number
               , to_tuple, to_list, to_map, to_term, to_binterm, to_pid, from_binterm
               , to_decimal, from_decimal, to_timestamp, to_time, to_datetime, to_ipaddr
  
positive.code: %% Unary custom filters
  expr_fun({Op, A}) when Op==safe_atom;Op==safe_binary;Op==safe_binstr;Op==safe_binterm;Op==safe_boolean;Op==safe_datetime;Op==safe_decimal;Op==safe_integer;Op==safe_ipaddr;Op==safe_json;Op==safe_float;Op==safe_json;Op==safe_list;Op==safe_map;Op==safe_name;Op==safe_pid;Op==safe_string;Op==safe_term;Op==safe_text;Op==safe_timestamp;Op==safe_tuple ->
      safe_fun(A);
  expr_fun({Op, A}) when Op==to_atom;Op==to_binary;Op==to_binstr;Op==to_binterm;Op==to_boolean;Op==to_datetime;Op==to_decimal;Op==to_json;Op==to_float;Op==to_integer;Op==to_json;Op==to_list ->
      unary_fun({Op, A});
  expr_fun({Op, A}) when Op==to_map;Op==to_name;Op==to_number;Op==to_pid;Op==to_string;Op==to_term;Op==to_text;Op==to_timestamp;Op==to_time;Op==to_tuple ->
      unary_fun({Op, A});
  
negative.code:         , to_ipaddr/1
          , to_name/1
          , to_text/1
          , list_to_binstr/1
          ]).
  
  -export([ concat/2
  