Teacher, in the example you gave:
function func2(param1, param2) {
param1 = arguments[0] ? param1 : 600;
param2 = arguments[1] ? param1 : 300;
}
This ternary operator, if I call it like this: func(0, 0,);
I pass in If the parameter is 0, it will actually be judged as failure, and param1 and param2 will be assigned values of 600 and 300
It is inappropriate to set default parameter values in this way. In fact, js now supports default parameters, so there is no need for such trouble (es6)