Cin object return value c++

Question

I woud like to ask what is return value of cin? I know it is istream object and when it is used in expression like if(!cin) there is actually called some function and I woud like to know what function it actually is. cin.fail() or cin.good() or.. Is if(!cin) same as if(cin.fail())?

http://stackoverflow.com/questions/5695146/what-is-cin-doing-inside-argument-of-if — Suvarna Pattayil, Oct 15 '13 at 15:35

masoud · Answer 1 · 2013-10-15T16:15:42.000

1

Yes.

cin overloads casting operators, and they return flag status fail().

A possible implementation:

operator void*() const {
    return !fail();
}

explicit operator bool(){
   return !fail();
}

bool operator!() const {
   return fail();
}

Look at here and here.

edited Oct 15 '13 at 16:15

answered Oct 15 '13 at 15:31

masoud

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Cin object return value c++

1 Answers1

Yes.

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