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expected primary-expression before .....

Hi guys,

I added this piece of code into the original one:

Code:

Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff() const

{

    return drag_->K();

}



Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff(const volScalarField& M30, const volScalarField& M20) const

{

    return drag_->K(const volScalarField& M30, const volScalarField& M20);

}

the compiler said:

Code:

twoPhaseSystem.C: In member function ‘Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::twoPhaseSystem::dragCoeff(const volScalarField&, const volScalarField&) const’:

twoPhaseSystem.C:291:21: error: expected primary-expression before ‘const’

     return drag_->K(const volScalarField& M30, const volScalarField& M20);

                     ^

twoPhaseSystem.C:291:48: error: expected primary-expression before ‘const’

     return drag_->K(const volScalarField& M30, const volScalarField& M20);

                                                ^

twoPhaseSystem.C:292:1: warning: control reaches end of non-void function [-Wreturn-type]

 }

 ^

make: *** [Make/linux64GccDPOpt/twoPhaseSystem.o] Error 1

Even I change it into:

Code:

Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff() const

{

    return drag_->K();

}



Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff(const volScalarField& M30, const volScalarField& M20) const

{

    return drag_->K(int A);

}

It crushed!!

But this is totally fine:

Code:

Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff() const

{

    return drag_->K();

}



Foam::tmp<Foam::volScalarField> Foam::twoPhaseSystem::dragCoeff(const volScalarField& M30, const volScalarField& M20) const

{

    return drag_->K();

}

So it must be something wrong with this:

Code:

return drag_->K(const volScalarField& M30, const volScalarField& M20);



or



return drag_->K(int A);

But I dont know where its wrong. Any comments is appreciated!
Thanks

Quote:

Originally Posted by sharonyue (Post 517166)

So it must be something wrong with this:

Code:

return drag_->K(const volScalarField& M30, const volScalarField& M20);



or



return drag_->K(int A);

Indeed.
You need to distinguish parameter passing and receiving.

When you receive a parameter in a function (blue, below), you must specify its type. You are already doing this.
When you pass a variable to another function (purple, below), you must solely pass the variable, without including its type in front: the compiler already knows its type. If you do put its type in front, you are declaring a new variable, which you do not initialize. That will result in a compilation error.

Quote:

Originally Posted by sharonyue (Post 517166)

Code:



Foam::tmp<Foam::volScalarField>  Foam::twoPhaseSystem::dragCoeff(const volScalarField& M30, const  volScalarField& M20) const

{

    return drag_->K(const volScalarField& M30, const volScalarField& M20);

}

So, you should do:

Code:



Foam::tmp<Foam::volScalarField>  Foam::twoPhaseSystem::dragCoeff(const volScalarField& M30, const  volScalarField& M20) const

{

    return drag_->K(M30, M20);

}

Exactly! Thank you very much!!!!!!!!!
bro!!