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Author Help a newbie
Nige

2005-12-06, 7:08 pm

Looking at some sample code.

I have a line, which calls a function

and the 3rd parameter is @Cells^[0]

whats do the @ and the ^ and the [0] indicate.

thanks


Nicholas Sherlock

2005-12-06, 7:08 pm

Nige wrote:
> @Cells^[0]
>
> whats do the @ and the ^ and the [0] indicate.


The whole thing gives you the address of (@) the fist item ([0]) of the
memory that cells uses (^). Read some tutorials on pointers.

Cheers,
Nicholas Sherlock
Jamie

2005-12-06, 7:08 pm

Nige wrote:
> Looking at some sample code.
>
> I have a line, which calls a function
>
> and the 3rd parameter is @Cells^[0]
>
> whats do the @ and the ^ and the [0] indicate.
>
> thanks
>
>

The @ generates an address of an item.
so lets break this down.

Cells is being treated like a pointer and
thus the use of ^ meaning that you are
fetching data via the pointer which is like
a road map giving directions of where the
start of the data which makes up the object
"CELLS" resides in.
Since it's obvious that Cells must not
be a pointer already to start with, using the
@ infront will generate a pointer address of that
object.
and the use of the [0] is like any other
array from that point on.
it will simply use the Pointer address as the
starting base with the an offset of what
ever in the [?] to calculate the distant to
move from the start of the pointer.



--
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

Bruce Roberts

2005-12-07, 7:05 pm


"Nige" <nkarnold@blueyonder.co.uk> wrote in message
news:Ihplf.160032$Es4.143191@fe2.news.blueyonder.co.uk...
> Looking at some sample code.
>
> I have a line, which calls a function
>
> and the 3rd parameter is @Cells^[0]
>
> whats do the @ and the ^ and the [0] indicate.


The code won't compile. In any case it is nonsensical. @Cells and Cells
mean the same thing as does Cells^ and Cells, presuming Cells is the name
of an array.


Riki Wiki Google

2005-12-11, 7:18 pm

Hoi Nige + others

When you post in a borland.public... news group you need to post on the
Borland news server to make everybody see it. Further, this news group
b.p.delphi do not officially exist.

Take a look here:
<http://tinyurl.com/8m5nw>
which links to
<http://delphi.wikicities.com/wiki/Delphi_Newsgroups>

DrChaos

2005-12-15, 7:02 pm

Nige wrote:
> Looking at some sample code.
>
> I have a line, which calls a function
>
> and the 3rd parameter is @Cells^[0]
>
> whats do the @ and the ^ and the [0] indicate.
>
> thanks
>
>

@ = adress of
^ dereferences a pointer
[x] is the x'th position in a list or array.
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