JS_ ','逗号

1,

function b1(){
    $S.Alert("b1");
}
function b2(){
    $S.Alert("b2");
}
function b3(){
    $S.Alert("b3");
}
function b4(){
    $S.Alert("b4");
}
~function(){
    return !1 ? (b1(),b2()) : (b3(),b4(),b1());
}()

2,

~function(){
    var a1,a2; 　　//如果写成 var a1 = a2 = 18; a2为全局变量;
    a1 = a2 = 18;
    $S.Alert(a1);
    $S.Alert(a2);
}();
$S.Alert(a1);

3,

var a = 1;
var b = 2;
$S.Alert((null,b === 2));　　//如果写成$S.Alert(null,b === 2) 返回null, b===2被无视了.
if(null,b === 2) $S.Alert("1");　　// 只考虑后面那个的ture,false;

4,

for(var i=0,j=10;i<j;i++){
    $S.Alert(i)
}

5,

var a = [1,2,3,4];
var b = {
    name:"a",
    age:"b"
}
function(a,b,c,d){}