A question about tagged functions

A question about tagged functions - Printable Version

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A question about tagged functions - Joey^ - 27.03.2013

So I found out that you can have functions with a tag, for example:

pawn Код:

Float:square(Float:a)
    return (a * a);

But if you compile this, the compiler will print out a warning:

Код:

: warning 208: function with tag result used before definition, forcing reparse

Then I found out that you have to use forward before the function, so:

pawn Код:

forward Float:square(Float:a);
Float:square(Float:a)
    return (a * a);

And now, the compiler will compile normally without any warnings. So, my question is: is it any better by using tagged functions or is it the same by using plain functions like this:

pawn Код:

square(Float:a)
    return (a * a);

Re: A question about tagged functions - Joey^ - 27.03.2013

******, thank you very much by explaining me this. I understand some things clearly now.

I've got one more question about parameters in the functions. Is it a big difference when using const with some parameters and not using?

For example:

pawn Код:

printMessage(const message[])
    return printf("%s", message);

printMessage(message[])
    return printf("%s", message);

Is there some kind of difference between those two codes? Expect that when using const that variable/parameter can't be changed in the function.

Re: A question about tagged functions - Sinner - 27.03.2013

Quote:

Originally Posted by Joey^

******, thank you very much by explaining me this. I understand some things clearly now.

I've got one more question about parameters in the functions. Is it a big difference when using const with some parameters and not using?

For example:

pawn Код:

printMessage(const message[])
    return printf("%s", message);

printMessage(message[])
    return printf("%s", message);

Is there some kind of difference between those two codes? Expect that when using const that variable/parameter can't be changed in the function.

const (Constant) means you can't alter the parameter. You're using a string so since you're actually passing a pointer to the address the first elemt of the string is located at rather than a copy of the variable (like you would with integers or floats) it would be possible to change the string. const prevents this.

So for example, doing:

pawn Код:

stock afunction(const string[]) {
    string[0] = '_';
}

Would give you an error, since you can't alter constant parameters.

pawn Код:

must be lvalue (non-constant)

Hope that helped.

Re: A question about tagged functions - Joey^ - 27.03.2013

Yeah, thought so. Thanks guys.