Declare variable inside or outside the loop?
If you don't do anything with the object reference, you should declare it outside the loop to avoid wasting resources on declaration on every loop pass. However, if you do something with the reference inside the loop, then you have to declare and create object inside the loop.
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Function-level constants - declare at top of function?
The two reasons for using a constant instead of hard-coding a value is for readability and so it can be easily found and changed later, right? So declare it where it would be most easily found later. Usually I find this is at the beginning of the function, class, or file - again, whatever scope makes sense.
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Is it necessary to declare PayPal income on the tax report?
In the US, for instance, hiding money in PayPal to avoid taxes is looked at as tax evasion, and illegal. Google "paypal tax reporting", it's not worth getting caught.
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Do you declare your car modifications?
Apparently many modified vehicles are being pulled over by police and issued penalties on improper or illegal modifications to their cars. However this is very confusing subject matter as to what is deemed illegal and what is deemed acceptable?
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Why do you not declare several variables of the same type on the same line?
Agree with edg, and also because it is more readable and easy for maintenance to have each variable on separate line. You immediately see the type, scope and other modifiers and when you change a modifier it applies only to the variable you want - that avoids errors.
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