Vector-class with template

Okay, this is actually C++ but i didnt want to open a new thread for it

basically i wrote a simple 3d vector class and i wanted to template it in the way you can pass in any 3d vector in its constructor:

PHP Code:

---

template< typename T >
class Vec3
{
    public:

        T x , y , z;

        template< class Tvec >
        Vec3( const Tvec& v );
};

template< typename T >
template< class Tvec >
Vec3< T >::Vec3( const Tvec& v )
{
    x = T( v.x );
    y = T( v.y );
    z = T( v.z );
}

//Needed useage (Bullet's btVector3 as example):

btVector3 v1 = btVector3( 1.0 , 2.0 , 3.0 );
Vec3 v2 = Vec3( v1 ); 


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The error:

Code:

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error C2228: left of '.x' must have class/struct/union
error C2228: left of '.y' must have class/struct/union
error C2228: left of '.z' must have class/struct/union

---

Thank you Kung :D

i did some more testing and changed the function from the constructor to a normal method called 'from' - voilà the error is gone
I dont know if its done right or if i did something on the constructor wrong...mhhh actually i would like to work with the constructor on there^^

PHP Code:

---

template< typename T >
class Vec3
{
    public:

        T x , y , z;

        //explicit to stop unlimited implicit typeconersations a la Vec3<int> v = randomType;
        //you have declare it this way: Vec3<int> v( randomType );
        template< class Tvec >
        explicit Vec3( const Tvec& v );
};

template< typename T >
template< class Tvec >
Vec3< T >::Vec3( const Tvec& v )
{
    this->x = T( v.x );
    this->y = T( v.y );
    this->z = T( v.z );
} 


---

seems to work

EDIT:
seems that my first example now compiles fine also.. ;(

@kung under me: heheheh we will see, give me some time xxP

Not even 20 lines and nobody understands C++ anymore, C FTW :>