Re: Function arguments: References vs pointers
Rune Allnor wrote:
{ Some info on this is given in the FAQ section 8. Presuming
the OP has read the FAQ... -mod }
Hi all.
Consider the two functions
void f(int& i)
{
i = 1;
}
void g(int* j)
{
*j = 2;
}
Both are fed an argument which specify an integer in the
calling program, they set the value of that integer to 1
and 2 respectively.
What are the practical differences - if any - between the
two versions of the function call?
I used to follow the rule "Use a reference if you can", since it is
usually safer (no NULL pointers), and allows for easier refactoring. For
instance, it is easier to cut and paste a compound statement to a
function body without the need to change every output value into a pointer.
However, there is one exception that I use. if you want to avoid
compiler pessimizations due to reloading of your pointer and references
after a child function call in your function body, then you might want
to use the __restrict or __restrict__ keywords indicating that the
pointer is not aliased. The problem is that Visual C++ does not support
__restrict to be used on references, which is a pity. So, a lot of times
I'm converting references to pointers in order to exploit this feature.
Gino
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