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Re: How to declare a function parameter to be optional?

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  Re: How to declare a function parameter to be optional? GilNajera <gilnajera@gmail.com> - 2011-02-09 12:22 -0600
    Re: How to declare a function parameter to be optional? Jens <jens.gustedt@gmail.com> - 2011-02-10 21:40 -0600
    Re: How to declare a function parameter to be optional? David RF <davranfor@gmail.com> - 2011-02-10 21:41 -0600

#493 — Re: How to declare a function parameter to be optional?

Hi!

On 7 feb, 22:58, Pushkar Prasad <pushkar.pra...@live.com> wrote:
> Hello All
>
> Is there a way to ensure that one of the function argument is set as
> optional. So that it is not mandatory for the caller to pass that
> parameter and yet if necessary can be used?

You must set a default value to that parameter when declaring the
function:

void myFunction(int parameter1, int optional_parameter=23);

All non optional parameters must precede the optional ones.

So, when you call myFunction using just one parameter, the second will
take the value of 23.

Hope this helps.
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#505

On 9 Feb., 19:22, GilNajera <gilnaj...@gmail.com> wrote:

> You must set a default value to that parameter when declaring the
> function:
>
> void myFunction(int parameter1, int optional_parameter=23);

what you describe is valid C++ but not C.

for a form to do such a thing in C, please see my answer.
Jens
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#508

On 9 feb, 19:22, GilNajera <gilnaj...@gmail.com> wrote:
> Hi!
>
> On 7 feb, 22:58, Pushkar Prasad <pushkar.pra...@live.com> wrote:
>
> > Hello All
>
> > Is there a way to ensure that one of the function argument is set as
> > optional. So that it is not mandatory for the caller to pass that
> > parameter and yet if necessary can be used?
>
> You must set a default value to that parameter when declaring the
> function:
>
> void myFunction(int parameter1, int optional_parameter=23);
>
> All non optional parameters must precede the optional ones.
>
> So, when you call myFunction using just one parameter, the second will
> take the value of 23.
>
> Hope this helps.
> --
> comp.lang.c.moderated - moderation address: c...@plethora.net -- you must
> have an appropriate newsgroups line in your header for your mail to be seen,
> or the newsgroup name in square brackets in the subject line.  Sorry.

void myFunction(int parameter1, int optional_parameter=23);
expected ‘;’, ‘,’ or ‘)’ before ‘=’ token

You're probably talking about c++
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