returning array size

[theAnswer]

hello,
Is there a way to implement a little function to return the size of an array
(not a string)?

Something like int size(int *array)

thanx

[Joona I Palaste]

Re: returning array size

theAnswer <i.got@what.it. takes> scribbled the following:[color=blue]
> hello,
> Is there a way to implement a little function to return the size of an array
> (not a string)?[/color]
[color=blue]
> Something like int size(int *array)[/color]

If the array is passed as an int * parameter, such a function is
impossible. However, if its declaration is in scope, then sizeof array
will return the array's size in bytes.

--
/-- Joona Palaste (palaste@cc.hel sinki.fi) ------------- Finland --------\
\-- http://www.helsinki.fi/~palaste --------------------- rules! --------/
"Nothing lasts forever - so why not destroy it now?"
- Quake

[Derk Gwen]

Re: returning array size

"theAnswer" <i.got@what.it. takes> wrote:
# hello,
# Is there a way to implement a little function to return the size of an array
# (not a string)?
#
# Something like int size(int *array)

The language does not define any way of extracting the allocated size
from a pointer to the first (or other) element. While an implementation
might (for example if pointer are segregated to different pages based on
allocation size), the portable solutions are to pass the length around
with the pointer or use a sentinel vector element.

--
Derk Gwen http://derkgwen.250free.com/html/index.html
Why are we here?
whrp

[Martin Ambuhl]

Re: returning array size

theAnswer wrote:
[color=blue]
> hello,
> Is there a way to implement a little function to return the size of an array
> (not a string)?
>
> Something like int size(int *array)[/color]

No. Please check the FAQ before posting.


--
Martin Ambuhl

[Leor Zolman]

Re: returning array size

On Sat, 07 Feb 2004 20:19:34 -0000, Derk Gwen <derkgwen@HotPO P.com>
wrote:
[color=blue]
>"theAnswer" <i.got@what.it. takes> wrote:
># hello,
># Is there a way to implement a little function to return the size of an array
># (not a string)?
>#
># Something like int size(int *array)
>
>The language does not define any way of extracting the allocated size
>from a pointer to the first (or other) element. While an implementation
>might (for example if pointer are segregated to different pages based on
>allocation size), the portable solutions are to pass the length around
>with the pointer or use a sentinel vector element.[/color]

If the OP chooses to pass the length along with the pointer, I could
show him a _real_ efficient implementation of size() ...
-leor

P.S. Have I gauged this right, such that it would be perceived as
humorous rather than sarcastic? I didn't want to put a smiley there
and prejudice the verdict...


Leor Zolman
BD Software
leor@bdsoft.com
www.bdsoft.com -- On-Site Training in C/C++, Java, Perl & Unix
C++ users: Download BD Software's free STL Error Message
Decryptor at www.bdsoft.com/tools/stlfilt.html

[Richard Heathfield]

Re: returning array size

Leor Zolman wrote:
[color=blue]
> On Sat, 07 Feb 2004 20:19:34 -0000, Derk Gwen <derkgwen@HotPO P.com>
> wrote:
>[color=green]
>>"theAnswer" <i.got@what.it. takes> wrote:
>># hello,
>># Is there a way to implement a little function to return the size of an
>># array (not a string)?
>>#
>># Something like int size(int *array)
>>
>>The language does not define any way of extracting the allocated size
>>from a pointer to the first (or other) element. While an implementation
>>might (for example if pointer are segregated to different pages based on
>>allocation size), the portable solutions are to pass the length around
>>with the pointer or use a sentinel vector element.[/color]
>
> If the OP chooses to pass the length along with the pointer, I could
> show him a _real_ efficient implementation of size() ...[/color]

Quite so. I near... but then I thought better of it.

[color=blue]
> -leor
>
> P.S. Have I gauged this right, such that it would be perceived as
> humorous rather than sarcastic?[/color]

There's a difference? Sarcasm is the lowest form of wit only because nobody
is beneath using it.
[color=blue]
> I didn't want to put a smiley there
> and prejudice the verdict...[/color]

Not putting smileys in often enough has got me into lots of trouble. :-)


--
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