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Initialization in with in for block

 
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Hello All,

I have a very simple and a silly doubt . why can't we declare a new variable inside for loop. Like

for(int i=0;i<5;i++)
int j=10; //No enclosing braces {}

After some analysis, I thought

int j=10; => int j; j=10; //Two separate steps

and since there is no block defined the above one is interpreted as

for(int i=0;i<5;i++)
{ int j;}
j=10; // Using un declared variable

Is my understanding correct, if so why should compiler separate both declaration and initialization.
 
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This isn't exactly an answer to the question that you asked, but I like the coding convention where you always use braces. This makes it easy. It's a "no-brainer" to always type braces for loops and such.

Kaydell
 
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Declaration of j was in for block,once the for block is finished the variable j is destroyed ,its a local variable .......hence using j outside this block will give an compiler error
 
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Leavitt & Chandra!!

What's the answer?
 
Anonymous
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Hi Yogvinder,

When ever compiler sees int j=10;
internally it breaks it into int j; j=10; thats why when there is no braces around int j=10; it got declared with in for loop and lost its scope outside the loop. Hence we get compiler error for accessing an uninitialized variable.
 
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