Am 26.06.2013 12:38, schrieb Michael Schnell:
On 06/26/2013 12:13 PM, Sven Barth wrote:
You do know that s2 will point to the same record of s1 after the
assignment? The contents of the string record are not copied, only
the pointer of s2 will change. See this example:
You are right (my testing program in pre-Unicode-Delphi does show
exactly this).
But what I wanted to show is, that here more is done but just managing
the reference count. Regarding the dispute I had with dodi, he thus is
right that the length is not exactly _copied_over_, but the pointer is
managed in a way that the same length (and content) is shown. (I admit
that he is correct calling this just "reference counting".)
Regarding the underlying discussion about RawByteString:
If exactly this is done when assigning a normal String variable to a
RawByteString Variable, it happens exactly what I suppose (and dodi
seems to deny): the dynamic encoding type of the RawByteString
(target) will be set to the encoding type of the normal String
(source). Thus the encoding type is _not_ lost and (in principle) when
assigning a RawByteString to a normal String, the library would be
able to check the actual dynamic encoding type of the source against
the (static=dynamic) encoding type of the target and do a conversion
if appropriate. IMHO this would be a very sensible behavior.
It's the whole use of RawByteString that the encoding is kept. For all
other string types the content will be converted. See also
compare_defs_ext in compiler/defcmp.pas around line 445 (look for "don't
convert ansistrings").
Regards,
Sven
_______________________________________________
fpc-devel maillist - fpc-devel@lists.freepascal.org
http://lists.freepascal.org/mailman/listinfo/fpc-devel
