struct testing {
    var value:Int
}

var test1 = testing(value: 6 )

test1.value = 2
// this works with no issue

var test2 = testing(value: 12 )

var testings = [ test1,test2 ]

for test in testings{
    test.value = 3
// here I get the error:"Can not assign to 'value' in 'test'"
}

如果我把结构改成类工作。任何人都可以告诉我如何可以改变结构的值。