Re: pesky Pointers !!

From: Rich (Someone_at_somewhere.com)
Date: 12/21/04 

Date: Mon, 20 Dec 2004 23:51:03 +0000 (UTC)

> '*pTest' is type 'string'
> Your function needs an argument of type 'string*' ('pointer to string').
> 'pTest' is type 'string*', and contains the address of 'sTest'.
>
> Write:
>
> StringTest(pTest);
>
Hi Thanks that worked, but I still dont understand why it worked, sorry :(

pTest looks just like a normal variable, which I thought was what a a
reference was used for ???

A reference as a parameter in a definition allows the programmer to pass
a reference without really knowing, i.e. no need to do &x or *x just x
and the function takes it as a reference instead of a copy.

 From what I have kearnt about pointers and syntax using pointers it is
fairly straightforward you read from right to left e.g

int* px // px is a pointer to an int

*px dereferences the pointer to get the value

&px gives the address that *px points to

hopefully I have the above right?

So then if a function expects a parameter string* s

This is saying I need a pointer to a string passed to me??

So I thought I needed to pass the pointer as an argument thus requiring
either the use of the * or & before the pointer to show that it is a
pointer I am passing.

by passing pTest just like that it looks like a normal variable name ??

e.g if I just called the pointer Test then it would be confusing.

Now I am completely confused again doh!!

BTW

I notice a couple of different C++ styles one which out tutor insists we
use but I dislike

she insists on this type of style for parenthesis

a [ 10 ] // array
func ( 10, 20 ) // function call

I have also seen
a[10]
func(10,20)

I prefer an in between like
a[ 10 ]
func( 10 ,20 )

I use this because having the parenthesis next to the variable or
function name makes it look like it is part of it rather having the
variable part then a space then parenthesis looks kind of odd to me, I
can understand the spaces after first parenthesis and before last
parenthesis but why do some people insist on having a space before the
first parenthesis as well???

I know style is a matter of preference, but sometimes I think too many
spaces makes it more difficukt to read than no spaces.

I try to voice this with our tutor but she insists on the all spaces
style, this style I know is popular with Java programmers, but when did
it become a style in C++??

TIA

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