CREATE OR REPLACE FUNCTION delete_element("varchar", _varchar)
  RETURNS _varchar AS
'
declare
  i integer;
  j integer;
  dpos integer;
  epos integer;
  count integer;
  dims varchar;
  element ALIAS FOR $1;
  array_in ALIAS FOR $2;
  array_out varchar[];
  null_array constant varchar[] := array[\'\'];
begin
  dims := array_dims(array_in);     %af_src_comm_0 
  dpos := position(\':\' in dims)+1;  %af_src_comm_1
  epos := position(\']\' in dims);    %af_src_comm_2
  count := substring(dims from dpos for epos-dpos); %af_src_comm_3
  
  j := 0;
  array_out := null_array;
  FOR i IN 1..count LOOP
    if array_in[i] <> element then
      j := j+1;
      if j = 1 then
        array_out[j] := array_in[i];
      else
        array_out := array_append(array_out, array_in[i]);
      end if;
    end if;
  END LOOP;

  if array_out = null_array then
    array_out := null;
  end if;

  return array_out;
end;
'
  LANGUAGE 'plpgsql' VOLATILE;