L505 wrote:
In short (don't pin me on the names or on exact details in special cases):
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
there was a reason I said this.
Assume you have a ansistring and you assign something to it
S := 'SomeString';
the compiler generates something like
DecStringRef(S);
S -> 'SomeString';
IncStringRef(S);
The DecStringRef() decrements the refcount and checks if the it reaches
zero. Ifso, the string is freed. The referencecounter of a strings lies
Why does it generate a DecStringRef before you assigned the string? What if it
is the
first time and you are already at 0, it can't decrement it to -1 can it?
Does the reference count start at 0, or 1?
A string is initially initialized as nil. DecStringRef checks if it is a
nil, if so, nothing is done.
In this case, it decrements 1 and increments 1, so we will always end up with a
very
simple, easy, solvable problem.
1 - 1 = 0
1 - 1 = 0
Nope, since the string was nil, it isn't decremented, so you end up with
a refcount of 1
That seems like it isn't doing anything useful, since we are incrementing and
decrementing by one, every time we assign a string.
What Jonas said was that the reference count would be 1 (one) when you pass it
to a
DLL. You are saying it will be 0 (zero).
I didn't say that. You assumed that the initial string was empty.
We have two people saying opposite things
here, so I'm really not sure what is going on. What would be logical to me, is
if the
reference count was 1, not zero.
It is 1.
Marc
I guess when I finally understand this science, I will write a diagram showing
how it
works in a Pascal procedure or function with comments beside each code snippet
saying
what the reference count is.
If there is a PDF file that explains this or some good website let me know. I
hate to
embarrass myself here (maybe other people are confused too, though).
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