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A function that returns a pointer on a function

Hi,

I need to write a function that returns a pointer on a function. Is it
possible, and which is the syntax ?

Thanks.
Boris

Jul 22 '05 #1
3 1141

"Boris Sargos" <bs*****@wanado o.fr> wrote in message
news:c6******** **@news-reader4.wanadoo .fr...
Hi,

I need to write a function that returns a pointer on a function. Is it
possible, and which is the syntax ?

Thanks.
Boris


Trying to do that without using a typedef is a real test of your
understanding of type declarations. The easy way is with a typedef

typedef void (*FUNC_PTR)(voi d); // or whatever

FUNC_PTR some_function()
{
...
}

It is however impossible to define a function that returns a pointer to
itself, that would mean an infinite recursion in the type of that function.

john
Jul 22 '05 #2
"John Harrison" <jo************ *@hotmail.com> wrote in message
news:c6ahbn$9pp kf$1@ID-> "Boris Sargos" <bs*****@wanado o.fr> wrote in
message
I need to write a function that returns a pointer on a function. Is it
possible, and which is the syntax ?
Trying to do that without using a typedef is a real test of your
understanding of type declarations. The easy way is with a typedef
Without typedef I think this is it:

void (*some_function ())();

This is a function some_function taking no arguments and returning a pointer
to a function taking no arguments and returning a void. It's similar to a
function taking a reference to an array of elements. But of course, what
you have below is cleaner:
typedef void (*FUNC_PTR)(voi d); // or whatever

FUNC_PTR some_function()
{
...
}

It is however impossible to define a function that returns a pointer to
itself, that would mean an infinite recursion in the type of that

function.

This makes sense, because of

typedef FUNC_PTR (*FUNC_PTR)(voi d); // or whatever

But what about

void (*)(*some_funct ion())();

Just guessing. Could be wrong.
Jul 22 '05 #3

"Siemel Naran" <Si*********@RE MOVE.att.net> wrote in message
news:c7******** ************@bg tnsc04-news.ops.worldn et.att.net...
"John Harrison" <jo************ *@hotmail.com> wrote in message
news:c6ahbn$9pp kf$1@ID-> "Boris Sargos" <bs*****@wanado o.fr> wrote in
message
I need to write a function that returns a pointer on a function. Is it
possible, and which is the syntax ?
Trying to do that without using a typedef is a real test of your
understanding of type declarations. The easy way is with a typedef


Without typedef I think this is it:

void (*some_function ())();


That's right.
This is a function some_function taking no arguments and returning a pointer to a function taking no arguments and returning a void. It's similar to a
function taking a reference to an array of elements. But of course, what
you have below is cleaner:
typedef void (*FUNC_PTR)(voi d); // or whatever

FUNC_PTR some_function()
{
...
}

It is however impossible to define a function that returns a pointer to
itself, that would mean an infinite recursion in the type of that function.

This makes sense, because of

typedef FUNC_PTR (*FUNC_PTR)(voi d); // or whatever

But what about

void (*)(*some_funct ion())();

Just guessing. Could be wrong.


Syntax error on my compiler. If it's not possible with a typedef I don't see
why you think it might be possible without a typedef.

john

Jul 22 '05 #4

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