That's:
var checkedpos=-1;
for (var i=0; i < 3; i++) {
if (document.form1.choice[i].checked) {
checkedpos = i;
break;
}
}
if (checkedpos == -1)
alert("Please check a thingy");
Sorry, I hate this TGML stuff...its very bad for program code, especially when I like to use "i"...