function and object types

function aa() {};
var bb = new aa();
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var dd = new function cc() {};
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aa.prototype.rr = 100;
cc.prototype.rr = 100;
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i wrote the code above that makes two functions and two object for
those.
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bb(object)<-aa(function),
dd(object)<-cc(function).
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i think it's all the same way to make an object for a function.
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but if u try to debug,
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bb object has rr right after "aa.prototype.rr = 100" statement
but dd deosn't have rr variable.
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can anyone explain it why?
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thanks in advance.