[fpc-devel] Encoded AnsiString
DrDiettrich1 at aol.com
Sun Dec 29 16:25:46 CET 2013
Michael Van Canneyt schrieb:
> On Sun, 29 Dec 2013, Hans-Peter Diettrich wrote:
>> Inspired by the current Lazarus discussion I'd like to learn more
>> about the current state of the implementation of the new AnsiStrings.
>> In case nothing has be done yet, I'd suggest to extend TAnsiRec by the
>> new codePage and elemSize fields (words). These can be zero for now,
>> so that the remaining codebase is not affected. Then it will be
>> possible to play around with encoded strings, using the codePage field.
> All this is done already a long time ago in trunk.
> We're way past that stage.
I'm very confused, didn't use FPC for a long time. Have to refresh
memory of all related procedures...
How do I instruct fpcup to checkout the trunk version? (Windows)
I tried to add an parameter fpcURL=trunk to the shortcut, is this correct?
How do I proceed (build, use in Lazarus...)?
Any links appreciated :-)
> Current stage is the creation of a unicode RTL, where all base
> file/string operations accept unicode strings. This is done too.
> Next step is creation of the unicode RTL, where "string" = "widestring".
> This will be combined with the dotted unit filenames, to be Delphi 2010+
How do I create source files for use with both versions?
> To allow people to choose, 2 RTLs will be created: one unicode
> (string=ansistring), one non-unicode (string=widestring).
> This will result (probably) in 2 paths:
> This is not decided yet.
> I planned the work in februari/march.
Where can I jump in?
>> A related question:
>> Why is the string length set to zero in NewAnsiString, when the
>> allocated Length is already known?
> Because the allocated memory length is not necessarily equal to the
> string length.
> If you have a string of length 50, setting the length to 25 will not
> discard and reallocate the memory block, but merely set the character
> length to 25.
This means that the allocated length is stored somewhere else, in the
memory block descriptor?
How can a user request an string of a specific allocation size?
I've heard that a mix of encodings converts the (concatenated) output
(RawByteString?) to CP_ACP, with possible losses. Is this correct?
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