Re: Localized Variable Declaration

[David Rasmussen <pinkfloydhomer@yahoo.com>]

martin.m.dowie wrote:
> "David Rasmussen" <pinkfloydhomer@yahoo.com> wrote in message
> news:3CF78D3D.3030400@yahoo.com...
> 
>>int whatever(int foo)
>>{
>>     ...
>>     ...
>>     { // local scope starts here
>>          int local = 42;
>>          ....
>>     } // and ends here
>>     ...
>>}
> 
> 
> now you have 3 lines not 1! ;-)
>

I think you miss the point, see below.

> 
>>So you can do the same in C++ as in Ada, and more. It's usually the
>>other way around. And usually Ada has a good reason for doing things
>>they way it does it. I just don't understand the justification for this
>>limitation. Consider this:
> 
> 
> All this is boils down to a choice of syntax and Ada is always going to
> look heavy on that count - is there any area that doesn't have Ada coming
> in with more keystrokes/source lines? It had never struck me as being
> terribly important, if a routine is getting complex enough to warrant nested
> within nested declarative blocks then I usually replace one or more with
> local
> subprograms (pragma Inlined if really necessary).
> 

I am not talking about the nested scopes. I am talking about the 
declarations. The declaration above is one line, not 3. The nested scope 
adds more lines, but that was just to show you that C++ has nested 
scopes as well.

In C++ you do this (nothing about nested scopes):

int main()
{
	cout << "Write two numbers: ";
	int a;
	cin >> a;
	int b;
	cin >> b;
	double c = a * b * 42.42;
}

The variables are declared when used, and not some centralized place in the
beginning. Furthermore, they are initialized as soon as possible. 
Whenever one
declares a variable and doesn't initialize it, an alarm should go off. 
This is inevitable even in small functions, in Ada, because variables 
have to be declared way before they are used.

/David