Chapter 2(Ex2_05.cpp) const double

Paul4936 · February 11th, 2011, 12:59 PM

If i'm use in Ex2_05.cpp

Code:

#define rollLength 12.0*33.0

isnt this is equal to

Code:

const double rollLength =12.0*33.0;

from book?

Will there be differences in the compiled program?
If not same, then which of this better to use for better perfomance of program?Or its no point?
Thank you in advance.
P.S. Sorry for my bad language.

gsallis · March 28th, 2012, 11:19 AM

There are a few reasons why I would recommend using the "const double" variant in favour of defining a macro.

1. I suspect performance is better as the data type has been explicitly defined.
2. It is more readable and clearer what the type and purpose of the variable is.