Is there some ninja trick to make a variable constant after its declaration?

Question

I know the answer is 99.99% no, but I figured it was worth a try, you never know.

void SomeFunction(int a)
{
    // Here some processing happens on a, for ex         


        

Answer 1

A pattern I used to use is to "hide" the argument with an _, so the code becomes

void SomeFunction(int _a)
{
    // Here some processing happens on a, for example:
    _a *= 50;
    _a %= 10;
    if(example())
       _a = 0;

    const int a = _a;
    // From this point on I want to make "a" const; I don't want to allow
    // any code past this comment to modify it in any way.
}

You could also use only const variables and make a function to compute the new value of a, if necessary. I tend more en more to not "reuse" variables en make as much as possible my variables immutable : if you change the value of something , then give it a new name.

void SomeFunction(const int _a)
{
    const int a = preprocess(_a);
    ....

}