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#1
May 6th, 2002, 02:24 PM
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Variable Declaration
Do all variables for a given program have to be declared at the beginning of that program?
I'm guessing yes cuz I get this error: Code:
`j' undeclared (first use in this function) when I declare the variable anywhere else. Anyone know offhand why all variable must be done in the beginning if this is the case?
__________________
- dsb -  Perl Guy
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#3
May 6th, 2002, 03:56 PM
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Language: C
I thought the question was pretty clear but here: Code:
main()
{
int a; // not a problem
// code
// code
// code
int b; // causes error
}
THere's no error though if I declare 'b' at the top of the main block(with 'a').
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#6
May 7th, 2002, 07:29 PM
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It isn't that you have to declare all variables at the beginning of the function, but you must declare it before you use it and be sure that you are declaring it in a block that it is being used in. You are always safer declaring it at the beginning of the function.
A common mistake is this: Code:
function foo(int a) {
int b;
if (a==1) {
//another function call
b = do_something(a);
if (b == a) {
int c;
c = do_something(b);
} else {
c = do_something(a); //this is illegal, c doesn't exist here
}
}
}
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