// the RegExp engine has a low limit on groups so
   // I can't use it to select all fields, only verify them
re:=RegExp(0'|^(\d+-\d+-\d+)| + 0'|\s+\d+\.\d+\s+-*\d+| * 24 + ".+$");
w:=[1..].zip(File("readings.txt"));  //-->lazy (line #,line)
reg datep,N, good=0, dd=0;
foreach n,line in (w){
   N=n;		// since n is local to this scope
   if (not re.search(line)){ println("Line %d: malformed".fmt(n)); continue; }
   date:=line[re.matchedNs[1].xplode()];  // I can group the date field
   if (datep==date){ dd+=1; println("Line %4d: dup date: %s".fmt(n,date)); }
   datep=date;
   if (line.replace("\t"," ").split(" ").filter()[1,*]  // blow fields apart, drop date
         .pump(Void,Void.Read, // get (reading,status)
            fcn(_,s){  // stop on first problem status and return True
               if(s.strip().toInt()<1) T(Void.Stop,True) else False
       })) continue;
   good+=1;
}
println("%d records read, %d duplicate dates, %d valid".fmt(N,dd,good));