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Nov 13th, 2008
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Why does this work?

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C++ Syntax (Toggle Plain Text)
  1. std::string s="s1";
  2. std::cout<<s<<std::endl;
  3. {
  4. 	std::string s="s2";
  5. 	std::cout<<s<<std::endl;
  6. };

Why can I have two variables with the same name existing like this?
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n3XusSLO is offline Offline
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Re: Why does this work?

it is becoz of the scope of the variable
one declare out side the function is in the Global Scope
and other one is inside the Function having the Function Scope
...
now how question is if the variable name is same then... how does it works...
Answer is ...
by help of scope operator(i am not sure it is operator or not sorry to say i forgot) "::"
if the variable is in the global scope the ::<variable>
if there is no ambiguity in the name of the variable then the scope resolution operator is not need ...

this thing comes handy in class..
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Rhohitman is offline Offline
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Re: Why does this work?

thanks
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n3XusSLO is offline Offline
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Re: Why does this work?

Where's the function? Wouldn't the {}s be ignored since there is no function or if statement or control loop associated with the {}s to generate a new scope?
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Nearly a Posting Maven
Lerner is offline Offline
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Re: Why does this work?

AFAIK brackets can be used without any function or if statement, simply as code-block.
They just come in handy for functions, classes, etc.
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Sci@phy is offline Offline
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Re: Why does this work?

Click to Expand / Collapse  Quote originally posted by Lerner ...
Where's the function? Wouldn't the {}s be ignored since there is no function or if statement or control loop associated with the {}s to generate a new scope?
ya ya, thanx for correcting...
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Rhohitman is offline Offline
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Re: Why does this work?

>>AFAIK brackets can be used without any function or if statement, simply as code-block.
They just come in handy for functions, classes, etc.

That would be interesting.
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Re: Why does this work?

Click to Expand / Collapse  Quote originally posted by Lerner ...
>>AFAIK brackets can be used without any function or if statement, simply as code-block.
They just come in handy for functions, classes, etc.

That would be interesting.
I'm stunned. Can somebody tell me if bracket section alone is by C/C++ standard?
Because, DevC++ mingw and Visual C++ Express 2008 both compile and execute properly:
C++ Syntax (Toggle Plain Text)
  1. #include <iostream>
  2.  
  3. int main(){
  4.     int a=5;
  5.     std::cout<<"Out of bracket:"<<a;
  6.     {
  7.         int a = 6;
  8.         std::cout<<"\nIn bracket: "<<a;
  9.     }
  10.     std::cout<<"\nOut again: "<<a<<std::endl;
  11.  
  12.     std::cin.get();
  13.     return 0;
  14. }
Providing output:
Quote ...
Out of bracket: 5
In bracket: 6
Out again: 5
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Sci@phy is offline Offline
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Re: Why does this work?

Maybe it's one of those things like it's valid to use OR instead of || or AND instead of &&, or that a comma is an operator, etc. But, yeah, it would be interesting if those who have access to a copy of the standard or know the relevant section of the standard would post a report.
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