implement CSV; include "sys.m"; include "bufio.m";	bufio: Bufio;	Iobuf: import bufio; include "csv.m"; init(b: Bufio){	bufio = b;} getline(fd: ref Iobuf): list of string{	rl: list of string;	for(;;){		(w, end) := getfield(fd);		if(rl == nil && w == nil && end < 0)			return nil;		rl = w :: rl;		if(end != ',')			break;	}	l: list of string;	for(; rl != nil; rl = tl rl)		l = hd rl :: l;	return l;} getfield(fd: ref Iobuf): (string, int){	w := "";	if((c := getcr(fd)) == '"'){	# quoted field		while((c = getcr(fd)) >= 0){			if(c == '"'){				c = getcr(fd);				if(c != '"')					break;			}			w[len w] = c;		}	}	# unquoted text, possibly following quoted text above	for(; c >= 0 && c != ',' && c != '\n'; c = getcr(fd))		w[len w] = c;	return (w, c);} getcr(fd: ref Iobuf): int{	c := fd.getc();	if(c == '\r'){		nc := fd.getc();		if(nc >= 0 && nc != '\n')			fd.ungetc();		c = '\n';	}	return c;} quote(s: string): string{	sep := 0;	for(i := 0; i < len s; i++)		if((c := s[i]) == '"')			return innerquote(s);		else if(c == ',' || c == '\n')			sep = 1;	if(sep)		return "\""+s+"\"";	return s;} innerquote(s: string): string{	w := "\"";	for(i := j := 0; i < len s; i++)		if(s[i] == '"'){			w += s[j: i+1];	# including "			j = i;		# including " again		}	return w+s[j:i]+"\"";}