false-positive error using std::functional in vs2015

Question

I have implemented some test functionals yesterday and everything compiled and worked fine without errors. Today i came back to my PC and my std::bind's are underlined red but compile without error. Seems like Intellisense and the compiler do not agree on the std::bind type. How can I fix this?

#include <functional>

class MyClass {
public:
    int doE() {
        return 0;
    }

    int doF() {
        return 1;
    }
};


void main()
{
    MyClass obj;
    std::function<int()> f = std::bind(&MyClass::doE, obj); // underlined red
    std::cout << f();
}

The error message is as follows:

Error (active)
    no suitable user-defined conversion from "std::_Binder<std::_Unforced, int (MyClass::*)(), MyClass &>" to "std::function<int ()>" exists
    functionals
    c:\functionals\functionals\thirdFunctionOnObject.h

I do have the same error type (Intellisense saying there is an error, but it compiles just fine) in more sophisticated code, where I used std::mem_fn().

Intellisense can usually be safely ignored. It's almost completely useless. — Edward Strange, Mar 08 '17 at 22:33
The Visual Studio IntelliSense parser is not the same as used by the Visual C++ compiler. IntelliSense can sometimes think that valid code is invalid and report it as an error. — Some programmer dude, Mar 08 '17 at 22:34
Try using a lambda instead of `std::bind`, as there are very few reasons to use `std::bind` over lambda other than obscure breaks caused by `std::bind` quirks, complex and unreadable error messages from `std::bind` mistakes, and general masochism? — Yakk - Adam Nevraumont, Mar 08 '17 at 23:00
I reworked my code to use lambdas and it's great. Readability is improved and no more error messages. Thanks Yakk! — coJetty, Mar 10 '17 at 14:16

score 2 · Accepted Answer · edited Apr 15 '17 at 19:45

2

Had the same problem with VS 2015 C++, I hate it. Microsoft drives me crazy.

For now I am using a nasty work around by moving the code to a static function. In your case it will be similar to the following:

class MyClass {
    // other code

    int doE () {
        return 0;
    }

    static int statDoE(MyClass * myClass) {
        return myClass->doE();
    }

}

edited Apr 15 '17 at 19:45

Jonny Henly

4,023
4
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answered Apr 15 '17 at 16:55

Max Pustovoyt

36
4

false-positive error using std::functional in vs2015

1 Answers1