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aaragon wrote:

> dim = read(filename);
> if(dim == 2)
> G2D* g_ = new G2D();
> else if (dim == 3)
> G3D* g_ = new G3D();
>
> // then use g_ to whatever is needed

Google for the Factory Pattern in C++.

--
Phlip
http://www.oreilly.com/catalog/9780596510657/
^ assert_xpath

Hi everyone,

Probably the solution to this question is trivial but I couldn't find
a clean way to do it. I try to have a variable depending on a
parameter that is read from a file at run time. Let's say something
like this:

....

dim = read(filename);
if(dim == 2)
G2D* g_ = new G2D();
else if (dim == 3)
G3D* g_ = new G3D();

// then use g_ to whatever is needed
....

The only way I managed to do this, is to have two pointers in the
code...=/
Is there a better approach? Thank you,

a²

aaragon wrote:

> Hi everyone,
>
> Probably the solution to this question is trivial but I couldn't find
> a clean way to do it. I try to have a variable depending on a
> parameter that is read from a file at run time. Let's say something
> like this:
>
> ...
>
> dim = read(filename);
> if(dim == 2)
> G2D* g_ = new G2D();
> else if (dim == 3)
> G3D* g_ = new G3D();
>
> // then use g_ to whatever is needed
> ...
>
> The only way I managed to do this, is to have two pointers in the
> code...=/
> Is there a better approach?

Yes. Use polymorphism. Derive G2D and G3D from a polymorphic base class.