[fpc-devel] String handling in trunk (was utf8 in 2.6.0)

[Michael Van Canneyt]

On Sat, 5 Jan 2013, Jonas Maebe wrote:

>
> On 05 Jan 2013, at 13:10, Michael Van Canneyt wrote:
>
>> On Sat, 5 Jan 2013, Jonas Maebe wrote:
>>
>>>
>>> On 05 Jan 2013, at 12:53, Paul Ishenin wrote:
>>>
>>>> ResourceStrings are stored as AnsiString type with 0 codepage (as I remember). Delphi now stores ResourceStrings as UnicodeString type. I think FPC will follow this in m_default_unicodestring modeswitch.
>>>
>>> It would probably even be better to always do that. At least I don't see a
>>> downside, other than slightly larger binaries (and that's not an issue in
>>> this case as far as I'm concerned; maintaining two separate resourcestring
>>> systems/handlers is just not worth the trouble).
>>
>> But it means that for
>>
>> Resourcestring
>>  AString = 'Something';
>>
>> Var
>>  S : Ansistring;
>>
>> begin
>>  S:=AString;
>> end.
>>
>> Always a conversion will happen.
>>
>> I do not think this is a good idea given that currently, String = Ansistring.
>
> String will always be shortstring or ansistring in the syntax modes in which that is currently the case. 
> And yes, it will involve a conversion in that case. 
> Just like every single constant string assignment to an ansistring in 2.6.x in case the constant string 
> contains non-ASCII characters and is part of a {$codepage xxx} file (because those strings are all stored 
> as unicodestring in the program there).

Judging by all the code that I have written during 14 years, there would never be a single conversion necessary.
This system would force them on me for every single use.

I do not think that the support of both ansi/unicode string resources is such a burden that it justifies that.

I admittedly have limited knowledge of compiler internals, but I cannot imagine that being able to store them 
in 2 formats (ansi and some form of unicode) is more than a matter of maintaining 1 flag per string, and writing 
a word instead of a byte.

All the other code, needed for conversions depending on codepage and whatnot settings, is necessary anyway.

Michael.