On 13/06/2015 15:24, Michael Van Canneyt wrote:
On Sat, 13 Jun 2015, Martin Frb wrote:
On 13/06/2015 15:12, Michael Van Canneyt wrote:
Note the 0 !
Secondly, the section about 'out' parameters is very old; there were
not nearly so much managed types at the time.
I will update it, I was just documenting the new string types
anyway. The above will nicely illustrate the point.
What about the (unverified) remark on the forum that delphi does it
different (apparently passing nil in that case)?
"const" is an exception. The purpose of const is to skip the ref
counting.
"Out" has a different purpose. Should it really create a dangling
pointer in a ref counted variable?
In your example you are lucky you got a refcount of 0. The memory is
after-all freed. you called the StringRefCount on a dangling pointer.
Anything could have happen.
No, the compiler *must* initialize it. Without that guarantee,
ansistring out parameters could never work.
Yes you are right. But that makes you example different. the value of
the "out" param passed in is nil (because of the initialization). So the
refcount of 0 is no surprise at all.
In my example the out param is fine too, but the other param (that gets
passed the same param on the callee side) is dangling.
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