implement Test; ##	venerable#		test expression# include "sys.m";	sys: Sys;	stderr: ref Sys->FD; include "draw.m"; include "daytime.m";	daytime: Daytime; Test: module{	init:	fn(ctxt: ref Draw->Context, argv: list of string);}; gargs: list of string; init(nil: ref Draw->Context, args: list of string){	if(args == nil)		return;	gargs = tl args; 	sys = load Sys Sys->PATH;	stderr = sys->fildes(2); 	if(gargs == nil)		raise "fail:usage";	if(!e())		raise "fail:false";} nextarg(mt: int): string{	if(gargs == nil){		if(mt)			return nil;		synbad("argument expected");	}	s := hd gargs;	gargs = tl gargs;	return s;} nextintarg(): (int, int){	if(gargs != nil && isint(hd gargs))		return (1, int nextarg(0));	return (0, 0);} isnextarg(s: string): int{	if(gargs != nil && hd gargs == s){		gargs = tl gargs;		return 1;	}	return 0;} e(): int{	p1 := e1();	if(isnextarg("-o"))		return p1 || e();	return p1;} e1(): int{	p1 := e2();	if(isnextarg("-a"))		return p1 && e1();	return p1;} e2(): int{	if(isnextarg("!"))		return !e2();	return e3();} e3(): int{	a := nextarg(0);	case a {	"(" =>		p1 := e();		if(nextarg(0) != ")")			synbad(") expected");		return p1;	"-A" =>		return hasmode(nextarg(0), Sys->DMAPPEND);	"-L" =>		return hasmode(nextarg(0), Sys->DMEXCL);	"-T" =>		return hasmode(nextarg(0), Sys->DMTMP);	"-f" =>		f := nextarg(0);		return exists(f) && !hasmode(f, Sys->DMDIR);	"-d" =>		return hasmode(nextarg(0), Sys->DMDIR);	"-r" =>		return sys->open(nextarg(0), Sys->OREAD) != nil;	"-w" =>		return sys->open(nextarg(0), Sys->OWRITE) != nil;	"-x" =>		fd := sys->open(nextarg(0), Sys->OREAD);		if(fd == nil)			return 0;		(ok, d) := sys->fstat(fd);		if(ok < 0)			return 0;		return (d.mode & 8r111) != 0;	"-e" =>		return exists(nextarg(0));	"-s" =>		(ok, d) := sys->stat(nextarg(0));		if(ok < 0)			return 0;		return d.length > big 0;	"-t" =>		(ok, fd) := nextintarg();		if(!ok)			return iscons(1);		return iscons(fd);	"-n" =>		return nextarg(0) != "";	"-z" =>		return nextarg(0) == "";	* =>		p2 := nextarg(1);		if(p2 == nil)			return a != nil;		case p2 {		"=" =>			return nextarg(0) == a;		"!=" =>			return nextarg(0) != a;		"-older" =>			return isolder(nextarg(0), a);		"-ot" =>			return isolderthan(a, nextarg(0));		"-nt" =>			return isnewerthan(a, nextarg(0));		} 		if(!isint(a))			return a != nil; 		int1 := int a;		(ok, int2) := nextintarg();		if(ok){			case p2 {			"-eq" =>				return int1 == int2;			"-ne" =>				return int1 != int2;			"-gt" =>				return int1 > int2;			"-lt" =>				return int1 < int2;			"-ge" =>				return int1 >= int2;			"-le" =>				return int1 <= int2;			}		} 		synbad("unknown operator " + p2);		return 0;	}} synbad(s: string){	sys->fprint(stderr, "test: bad syntax: %s\n", s);	raise "fail:bad syntax";} isint(s: string): int{	if(s == nil)		return 0;	for(i := 0; i < len s; i++)		if(s[i] < '0' || s[i] > '9')			return 0;	return 1;} exists(f: string): int{	return sys->stat(f).t0 >= 0;} hasmode(f: string, m: int): int{	(ok, d) := sys->stat(f);	if(ok < 0)		return 0;	return (d.mode & m) != 0;} iscons(fno: int): int{	fd := sys->fildes(fno);	if(fd == nil)		return 0;	s := sys->fd2path(fd);	n := len "/dev/cons";	return s == "#c/cons" || len s >= n && s[len s-n:] == "/dev/cons";} isolder(t: string, f: string): int{	(ok, dir) := sys->stat(f);	if(ok < 0)		return 0; 	n := 0;	for(i := 0; i < len t;){		for(j := i; j < len t; j++)			if(!(t[j] >= '0' && t[j] <= '9'))				break;		if(i == j)			synbad("bad time syntax, "+t);		m := int t[i:j];		i = j;		if(i == len t){			n = m;			break;		}		case t[i++] {		'y' =>	n += m*12*30*24*3600;		'M' =>	n += m*30*24*3600;		'd' =>	n += m*24*3600;		'h' =>	n += m*3600;		'm' =>	n += m*60;		's' =>		n += m;		* =>		synbad("bad time syntax, "+t);		}	} 	return dir.mtime+n < now();} isolderthan(a: string, b: string): int{	(aok, ad) := sys->stat(a);	if(aok < 0)		return 0;	(bok, bd) := sys->stat(b);	if(bok < 0)		return 0;	return ad.mtime < bd.mtime;} isnewerthan(a: string, b: string): int{	(aok, ad) := sys->stat(a);	if(aok < 0)		return 0;	(bok, bd) := sys->stat(b);	if(bok < 0)		return 0;	return ad.mtime > bd.mtime;} now(): int{	if(daytime == nil){		daytime = load Daytime Daytime->PATH;		if(daytime == nil)			synbad(sys->sprint("can't load %s: %r", Daytime->PATH));	}	return daytime->now();}