%ignore          "^#(.*)";
%token Comma     "\,";
%token Value     "[^\n\r\,]+";
%token Break     "\r(\n?) | \n";

%start document;

%%

// with optional last break
document
  : rows Break
  | rows
  | /* empty */
  ;

// each row seprated with one break
// and optional last space
rows
  : rows Break row
  | row
  ;
                                                                                                                                                                               
// values separated by spaces
row
  : row Comma column
  | column
  ;

// allow empty columns
column
  : Value
  | /* empty */
  ;