Re: A question about efficiency

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Regarding efficiency, if you pass a parameter by reference because you only
want to avoid the copy, it's better to have a parameter which is a const
reference.

void func2(const float &f, float &g)
{
g = f + 10;
}

Doing this, the call can be made both on a const and non-const f object,
even a literal value.
As a side effect, it allows implicit conversion, for instance from int

In func2, g is then documented as an in/out parameter.

As Uli has suggested for his function add_10, func1 could be write as :
float func1(float f)
{
return (f+10.0f);
}
for an object more complex than a float the compiler may optimize the code
with the "return value optimization" which avoids the creation of temporary
objects.

Fred




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