Re: Variable scope problem

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Variable scope problem

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Join Date: Sep 2004

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Narue

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Expert Meanie

Re: Variable scope problem

Sep 11th, 2007

>Provided I cannot make define the object globally or at the start of main().
You have to define a variable before it's used, and you have to define a variable within a visible scope. What you're doing is illegal because g1 is defined in a nested scope but used beyond that scope. It has to be like this:

Help with Code Tags

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int main()
{
  // ...
  Graph g1;

  if ( var )
    g1 = CreateGraph<Graph> ( vertex, edge );
  else
    g1 = CreateGraph<Graph1> ( vertex, edge );

  numvertex ( g1 );
}

>Provided I cannot make define the object globally or at the start of main().
If the unnamed block trick doesn't count, you're SOL:

Help with Code Tags

(Toggle Plain Text)

int main()
{
  // ...

  {
    Graph g1;

    if ( var )
      g1 = CreateGraph<Graph> ( vertex, edge );
    else
      g1 = CreateGraph<Graph1> ( vertex, edge );

    numvertex ( g1 );
  }
}

However, I fail to understand why you have this restriction. Perhaps you can enlighten us as to what program requirements are stopping you from defining a variable in the correct scope?

I'm a programmer. My attitude starts with arrogance, holds steady at condescension, and ends with hostility. Get used to it.

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Re: Variable scope problem

Variable scope problem

Re: Variable scope problem